....But surely my opinion will be held by the vast majority of other people.
Ahem. Anyways, I think that you will probably have more time in the park Friday and Saturday than you think. FIRST is buying out the park, after all, and they would realize that shutting the park down 2 hours after pits close would be silly.
As for entertainment near the hotels, I have yet to see a list of the hotels, but I'd be happy to make up a map of entertaining locales near the Dome and the package hotels.
Also, I can compile a list of dream coasters I'd love to cram into a park as well. The real question is whether the ride selection at Astroworld is really that much worse than the entertainment available at WDW. While the miscellaneous shows and tours aren't as good, I think the coaster selection is much better.
Finally, the Crawfish Festival was apparently Apr 12-13 last year in Kemah, so if it works out the same this year, you could always do that on sunday.
Edit: Take back the cornfield statement! I just read "Children of the Corn," and I don't like the implications.