I have an additional comment on the topic of signing Gary Walker.
I think that one of most difficult positions to draft for is defensive line. There have been a lot of first round picks who just don't pan out (it's so prevalent, I don't think I need to list them all), which also creates a lot of dead, or underutilized cap money. Some may come around after a few years, but still, drafting D-lineman in the first round represents risk.
I think the Texans can still be considered to be a franchise that is building it's base. Signing young lineman like The Baire and re-signing Walker so they can use their highest picks for QB, WR and CB makes sense. It also provided the chance for immediate improvement over last year. I hope they can pick off another 4 year d-lineman next year to deepen the position.