Her availability this year.
HLSR has a wish list, and they pay attention to who is charting, who is touring well, etc... They stack rank and start reaching out well in advance. Some bands have standing invitations and work well with the staff. Others are permanently banned. Some bands have tours already booked and can't work around it. Others don't want to perform because of beliefs (such as cruelty to animals - not kidding). Others don't want to perform because they aren't comfortable in the setting (having everyone so far away. It definitely bothers some acts. New stage and other things have helped over the years).
You are always going to see similar acts year over year. Most up-and-comers don't fill up the stadium and/or have the right connections to be invited (and are too big for the Hideout/Wine Garden stages). #1 goal of the show is money. If they are not going to sell out or come close, the show isn't too interested.
The rodeo has spent tons on diversity studies, and is always looking for ways to include all aspects of Houston. The big issue there is that first and foremost, this is a livestock show and rodeo event, and that is not for everyone.
Best thing this year is to head out early on the 11th, grab free drinks at the poultry junior market auction (maybe help out the kids), then wander over and see Turnpike.
And Go Tejano Day is a nightmare for committee members just from the sheer size of the crowd. Best thing to do is sit in a suite and drink tequila all day.*
*These views are my own and do not reflect the views of HLSR is any way, shape, or form. (in case tx 3 putt was wondering)