Serious reply: Texas players are built for speed, not power. Louisiana players, on the other hand, are just plain mean and large. Mississippi, Bama, and Georgia linemen are large and powerful. Florida is a state - like Cali - that produces lithe, athletic players, much like Texas. Unless things change at the high school level, the players produced in Texas are going to be best suited for the skill positions: QB, receiver (all types), running back, defensive back; positions that best utilize speed and size combinations for creating mismatches.
The problem, therefore, is at lineman; Garrett - although beastly - isn't large enough at this stage to be an aggressive, run-stopping lineman, he's much more of a rush end or 3-4 rush linebacker. Possibly the best solution is to start recruiting linemen from areas that produce the biggest and meanest ones (not necessarily the most athletic): traditional Big Ten areas like Wisconsin, Ohio, and Michigan, for instance, and from Southern states like Georgia, Alabama, Mississippi, and Louisiana. Don't even need the absolute best ones, just ones that are big, mean, and athletic enough to pull when needed; steal just one four-star player from each area - two or three a year - and eventually the program will be fully stocked with large, road-grading SEC-style linemen. Texas linemen should probably only be looked at in situations where you need an athletic pass rush specialist, or someone who can drop into a fire zone and cover for a short period of time; offensively, you might want to consider a four-star player per year as a key backup, swing tackle, or oversized tight end in jumbo packages, or someone you develop just hoping he turns into something special (at worst, he's a solid backup and can contribute in a pinch).
It's an ironic situation to be in, because Texas O-linemen have been generally outstanding over the years; nowadays, they've simply lost that physical, aggressive nature needed for SEC play and have become soft and weak-minded (a harsh criticism, but true until they start proving me wrong on the field of play).
By the same token, Texas linebackers are best suited for coverage roles; unless you can find one that's between 230 and 260 and can run, look to the South and California for linebackers. The spread has depleted the state of almost all elite linebacker talent and moved those players to safety and weakside rush end. The proof is in the product: Texas linebackers simply cannot hold up against the run, especially not in the SEC, so the solution is to ignore the talent pool except for two to five potential targets every year (and then only one or two serious signees a year) while looking elsewhere; at this point, a large four-star linebacker from, say, Georgia is a superior player to all but the most exceptional five-star Texas linebackers (like Malik).
Texas DB's, by contrast, are some of the best in the nation, right up there with Florida and Cali. Develop the best ones, and they'll be as large - if not larger - than most receivers and running backs and every bit as physical and athletic. In this respect, the spread has worked wonders at the high school level for developing Texas DB's. The problem with this team is that they were all forced to play far too early out of utter, job-saving desperation, and the staff is still feeling desperate and playing the kids before they're ready; they all need to be redshirted and get muscle on them until they're - at minimum - 200 to 220 lbs. each. This staff (and the previous one) simply failed the kids by playing them too fast and never giving them a chance to really learn the game and get bigger.
On the flip side of the discussion, A&M's receivers are absolutely gargantuan; they tower over defensive backfields and make the DB's look like midgets. Unfortunately, most of them have had problems with drops, and for whatever reason either have never learned how to run proper routes, can't get on the same page with the QB, or just don't have the shake to get open. Hopefully they figure it out, because this receiving corps is simply massive in stature.
At tailback, size is irrelevant; small backs can be very successful (Gordon's barely 210), just like big backs... what matters is your scheme. Size is also irrelevant at QB, what matters is their innate skill.
In the end, I wonder why the coaches never resorted to a cut-block zone scheme to compensate for the offensive line's inability to handle larger SEC lines. The Gibbs cut scheme is simply the best there is and makes inadequate lines produce strong run games no matter where it's been implemented at. If it were me, I would give no mind to the supposed "risk of injury" (the scheme, in fact, does not cause more knee injuries than other schemes and I think, in fact, also has a lower injury rate against it than others) and run it simply because it always works.
Nothing can be done for the linebackers and interior linemen, though; Texas players just aren't big enough, unless six players of Malik Jefferson's caliber come through here. D-line is hopeless with Texas players (it'll always be undersized and have to resort to stunts and help from linebackers to get the job done).
A comparison of other SEC schools to A&M's and where their starting offensive lineman come from (all information comes from Ourlads.com or Rivals):
(left to right, LT LG C RG RT, bolded for players from Texas, italicized for Big Ten/SEC/Northern regions; average weight of starters in parentheses)
Alabama: LA MD OH MD GA (334.8)
Florida: NC DE GA GA FL (314)
Ole Miss: FL MS TN MS IL (309.8)
MSU: AL MS LA MS Quebec (311)
LSU: LA GA LA IL LA (319.6)
Ark: CO CA AR FL AR (328.2)
Auburn: TN FL AL AL FL (304.8)
Georgia: FL GA GA MD GA (301.8)
Missouri: TX TX MO ND TX (306)
Tennessee: TN FL OH TN TN (303)
Vandy: TN IL TN TN FL (306.4)
Kentucky: KY KY IN FL FL (303.4)
South Carolina: NC SC NC FL SC (310.4)
TAMU: TX TX TX TX TX (302.2)
With the singular exception of Mizzou, there is absolutely no representation at all from Texas on opposing SEC offensive lines (listed starters only). Look at all that italic, though; elite schools like Bama and LSU have figured out that you have to poach the Big Ten for top offensive line talent. Incidentally, they're also among the best in the nation in the trenches. That's no coincidence. A&M, on the other hand, has been bullied ever since they entered SEC play, and it took Johnny to cover up their deficiencies in toughness and raw power; only occasionally have they looked decent, if not overpowered their SEC opponent.
That being true, they tend to overwhelm opponents from other conferences. The toughness problem is primarily an SEC issue.
The same for defensive lines:
(bolded for players from Texas, italicized for Big Ten/SEC/Northern regions)
Alabama: VA TX NC (285.67)
Florida: FL FL NC FL (275.25)
Ole Miss: SC GA MS MS (276)
MSU: LA MS MS GA (268.75)
LSU: LA NE LA TX (272.75)
Ark: AL AL TX AL (269.5)
Auburn: GA GA GA SC (293.75)
Georgia: GA GA GA GA GA (290)
Missouri: MO IO PA MO (270)
Tennessee: TN FL MI FL (267)
Vandy: TX MS TN (291.67)
Kentucky: KY CA FL AL (286.25)
South Carolina: SC NC SC GA (295.5)
TAMU: LA CA LA TX (272)
Look at all them italics. I'm not considering Nebraska historic Big Ten country right now, though. A'Shawn Robinson - Bama's NT player - was a five star recruit and is listed at 320. At LSU, Danielle Hunter from Katy was a four-star recruit, and is an outlier at a lithe 240 pounds. Taiwan Robinson (Arkansas) was a 247 Composite four-star player, and also an outlier at interior lineman at a trim 260. Adam Butler (Vandy) was a three star, but listed at 300-plus.
Georgia, strangely, only lists two starters at lineman on defense, but all five players listed on their depth chart are from Georgia. Every last one.
At A&M, Obioha was a three-star and is listed at 255; I-Rod was a 3/4 and is listed at 290. Alonzo was a 3 star and weighs in at 290-plus. Myles, obviously, was a five-star and would be the no. 1 draft pick if he declared right now; he's listed at a svelte 255, a weight better suited for rush linebacker in a 3-4 scheme. It's actually interesting that half of A&M's line is from Louisiana, but neither were they heralded recruits. 'Zo was the most heralded (not including Myles), but hails from Cali.
A deeper look into the average offensive line weights:
Every SEC school is over 300, and the mean average looks around a bit over 300 for the entire league, so the Aggie offensive line isn't exceptionally small by any stretch; the problem then is attitude, not size on offense.
An interesting look further at the defensive line average weights:
The overall average weight of the lines across the SEC - not including A&M - is 280.2. A&M's line, therefore, is slightly undersized per league average, but not by that much, relatively speaking. Including A&M, the number shifts down to 279.61. In fact, there are a number of teams just as small if not smaller: MSU, Arkansas, Mizzou, and Tennessee are all smaller than A&M going by the listed starters, and elite teams like LSU and Florida (defensively) are in the same range. Going by the entire defensive rotation versus the rest of the league's starters, however, A&M averages out to 265.5, which is easily the smallest in the league. The problem, though and again, is attitude, not so much size.
Even at linebacker, the league average is actually about at 230 or even 220; linebackers tend to be in the 220 to 240 range, with only a handful of teams running out heavy, 260-pound linebackers. LSU's linebackers are very small - the size of large NFL safeties - but just play meaner and bigger than their size, on top of playing very sound football.
Long story short, the team overall is smaller than average, but not by as much as people think; the defense especially looks smaller contrasted with the larger offenses they go across from, but this is a leaguewide phenomenon... only Alabama looks large compared with opposing offenses. The defensive line and the linebackers are especially small, exacerbating the problem when they're lined up across from the 300-pound monsters they have to beat on any given play. Only one starting SEC offensive lineman is smaller than 280, and he's still as heavy as most SEC starting interior linemen. A&M has some of the smallest interior linemen in all the SEC, but their outside ends are in the average range leaguewide, and are actually larger than LSU's ends by a small margin.