My suggestion is to apply this year (if you're open to attending a less prestigious TX school) and not wait for a new MCAT since the delayed application is likely to damage you more than a score that is merely adequate. Apply to EVERY single TMDSAS school. (Houston is rumored to auto-strike every student who doesn't.) If you're stuck on Houston or UTSW, then you'll probably need a higher MCAT and yes, it will cost you a year.
Based on what you've written, I would expect you would receive a few interview invitations and it will be the interview that makes or breaks you this year.
If by JH, you mean Johns Hopkins, and this is where you did your undergrad, then you may receive a slight bump on your GPA (which is very good in any case) since they're notorious grade deflators.