Located in Georgetown. I'm at a crossroads on what to do. See pics below. Bermuda 419 Tiff. Moved into this new home build 2 years ago.

Thatched it last November. Treating the weeds now. My questions are related to the grass only as I will take care of the weeds and apply pre and post emergent.

1) Is the grass too thin to come back this spring? If it does come back, will it be patchy?
2) What do you suggest I do now to help it get thicker?
3) Am I at a point where I just have to resod? This area is 6.5k square feet so it's a big decision point

What did it look like last year? I think you will have the whole growing season to see what it does because you'd probably want to re-sod late summer early fall. Just looks dormant to me.

Last year was great, but we only watered about 20 minutes per zone per week.

Any other opinions?

Looks like all the rain has cleared a lot of the thatch out for you! Maybe some aeration to break up the soil a bit, but yes see how it looks this spring/summer.

Cut it as low as you can at the first sign of green, lots of fert and aerate it.

Wait until nighttime temps are consistently in the 60s and fertilize with 21-0-0(ammonium sulfate) 1/2#N/1000 sq ft one week and 44-0-0(urea) at 1/2#N/1000 sq ft the next week. You'll need to water in each of those apps. I would also add a good Organic fertilizer as a base - there are lots of good options. Milorganite is generally readily available and there are plenty of other options people will recommend - Medina, Maestro Gro, Sustane, etc.
After a month, find a good slow release N(methylene urea, various coated products, polyon) fertilizer and put it out at 1-2#N(depending on the N source). This should be good for around 2 months(depending on the source).

I personally believe it doesn't do much good to fertilize until the nighttime temps are in the 60s.

One 50# bag of 21-0-0 will give you about 3 apps at 1/2#N/app for 6500 sq ft.
One 50#bag of 44-0-0 will give you about 6 apps at 1/2#N/app for 6500 sq ft.
You can get these at a feed store. Probably can get the 21-0-0 at HD.

You can put out more #s of N with each of these sources at a time, but if it is raining during that time(hopefully for you) the N will leach thru the soil before the grass can use it.

Mow short and watch it spread and grow!

Judging by the pictures you're gonna have serious problems this spring/summer. I'm guessing you turned your water completely off for several months last summer/early fall during the Williamson Co. water restrictions

Why did you dethatch in November? I would think that's something you wouldn't do any later than late Summer so that your grass can recover afterwards?

Otherwise, nothing much you can do now except wait for temps to warm up and see what comes back around April or so.