Good luck RR.
You've done some research. I hope you understand that there are different levels of select ball. In the Houston area Nations is the biggest organizations that youth tournaments are played under. Other places are probably USSSA. For nations, the levels of youth ball are metro (recreational), select, elite, and premier (this level starts at age 10). For USSSA, they go A, AA, AAA , and major (I have less experience with this organization). There is a ton of money that is earned every weekend hosting tournaments. Do the math and I bet you can see a weekend tournament that grossed about 24,000 in entry fees. And there are tournaments all over the place.
We started off playing recreational ball with team of very athletic kids. We realized my son enjoyed playing baseball and wanted to play at a more serious level. We joined a team involved with an organization at age 8. These were all dads that coached the teams. I found the kids not to me more athletic (but they were good), but they were far more polished. It took about a year of work for us to catch up.
The first team we were on played mainly at the select/AA level. We could find all the tournaments we wanted in the Houston area. We rarely traveled anywhere. In the fall, we worked out a little bit, but most kids primarily played football, soccer and basketball
At the younger ages (through 12-13), the top level teams (premier/major) will be made up of big kids who develop earlier physically, but you can catch up in high school - sometimes.
The big problem with dad coached teams is they tend to be a vehicle that showcases their son and the training as compared to someone who played collegiately or professionally is usually not as good. After a couple of years we wound up playing for a guy who played minor league ball and he taught us a lot. My sons still uses things he learned from that guy today.
We still played in the Houston area, except for a few occasions. All the families and kids had a blast one year playing a spring break tournament in Phoenix. Hung out by the pool, went to spring training games, and played baseball. There are tons of places along the gulf coast (Florida, Alabama) that sponsor "World Series" One thing we missed on that many select kids do is a "World Series in Cooperstown for 12 year olds. That is supposed to be a great experience.
Now, my son finished his freshman year in high school and is on of one of those teams in the link to the Premier League. If he wants to work hard he may be able to play collegiately - but at what level, who knows. Right now it is more about working hard to get better and having fun playing. I don't know the San Antonio area but I would say that in Houston, if you feed into a high school that has a competitive program, if you aren't playing at least the elite/AAA level by age 12 or 13, you will have a hard time making the high school team, and the skills can't be developed overnight.
Final note, if you are looking at an academy, check their reputation. Many of them have a top level team and other teams that are just meant to help pay the bills. In checking their reputation, find out whether they cut kids mid season. Some places you are on the roster unless they find someone they like better. The first team we played for had three kids who were cut mid season from another team the year before at age 7. How ****ty is that? You want someone who really has your son's development in mind and is not just chasing trophies.