A Busch Gardens in Texas would be interesting. DFW has the original Six Flags which is very large and one of the nicest in the chain and San Antonio has Six Flags Fiesta Texas which isn't as good but has some of the best Topography of all the chains as it's in the start of the hill country so it's built into mountains.
Then you have Seaworld, Discovery Point (Dolphins) and Aquatica in San Antonio as well. Discovery Point is nice, and the Aquatica is awesome. San Antonio is certainly the "tourist" place in Texas. 3 hrs from Houston, 4 from DFW, 1 from Austin.
And the San Antonio location has a decent amount of land surrounding it- but don't believe it's enough for a full fledged Busch Gardens. If they found a way to add that and 1 (maybe 2) on-site hotels- that would be an incredible trip. And the sea life in the park certainly doesn't bother us Texas folk
The way Seaworld utilizes Sesame Street is embarrassing. It's the worst part of the park- all concrete, terrible rides, no themeing anywhere, worn down etc. Every other area is better themed and better landscaped. So if they gave that a fully realized area in addition to a Busch Gardens park- that could be a very nice "poor mans Disney"