Great thread and good insight here. Some of this might have been covered, but a few notes:
Dallas - will keep growing forever, and lots of companies moving there. If you can find "deals" it's not bad.
Houston - not much to add here. Cool town, but with humidity, bad soil, hurricanes/floods, and mosquitos it's got some detractors. Decent market and cash flow, but need to buy in the right area.
Austin - lived here for 20+ years. Awesome town, but the deals are long gone. Even in the "less desirable" neighborhoods.
San Antonio - agree here with the positive sentiment about SA. Big town, lots of character, and slightly easier to find deals than the other big cities. Not as trendy as Austin, but has several large employers (HEB, Whataburger, USAA) and multiple military bases.
El Paso - Cool town and close to lots of cool outdoor activities. Lots of growth, but many people are not really sure where it is coming from. There are a lot of restaurant and entertainment chains moving in (Alamo Drafthouse, TopGolf, etc) but there aren't many jobs outside of medical and service industry (lower paying). Even thought it's a lot cheaper than the other big markets, I think it is a bit inflated. Also, some of the highest taxes in the state.
I'd agree that the area between the 4 big cities is best. Nothing between Houston and Dallas or Houston an SA, but between SA and Austin is probably idea. Waco is not bad, but has seen a lot of appreciate due to all the Chip and Joanna nonsense.
Also, for out of state investors, when we say "high property taxes" we mean 2.3% to 3%. That has obvious implications for cash flow, so plan accordingly.