I'm certainly no expert on the property tax laws in Texas, but anecdotally, there don't seem to be any "homestead" provisions that would limit or cap increases on your property taxes on your paid-for home. So assuming that you move to a less-expensive home, your property tax bills should go down. Hopefully, that smaller home will be less expensive than your current, larger house, allowing you to bank some of the equity from your current house.
From a financial standpoint, assuming that you move to a smaller, cheaper home, I don't see any issues, and there'd be less maintenance and yard-work, to boot. Seems like a no-brainer to me (assuming my many assumptions are correct, which is no sure thing).