Lots of options
If you are a devoted carnivore, consider Cured which is also at the Pearl. Ate there with an out of town visitor the other night and it was charcuterie heaven. Their cocktails are pretty impressive, too. Or if you are decidedly after steak, go for the rib eye at Midtown Arcade, also at the Pearl - I am not especially a fan of rib eyes, but theirs was memorably delectable. Pair it with the lobster soft taco starter and prepare your taste buds for ecstasy. Good wine list, too.
If you are reluctant to stray far from the Riverwalk to satisfy your meat craving, the Hyatt Regency (the "old" Hyatt property downtown) has restyled their house resto as Q and it garners very positive reviews.
Should you have time remaining after your five minute visit to the Alamo and wish to savor some good Mexican, stay as far away as possible from Mi Tierra and the other El Mercado tourist traps. Head, instead, to La Paloma Blanca on Broadway or La Fonda on Main (but not other places named La Fonda.)