Hi:
I'd like to point out an option I've heard good things about (but haven't gotten to do), for when you're more experienced (I don't mean that in any patronizing way; read some forum threads about the trips, and if you disagree, so be it). A little quick routing on Google Maps suggests you're under 4 hours from Freeport, Texas, IIRC.
That's where you'll find a live-aboard call the M/V Fling, featuring short trips to the Flower Gardens. Undercurrent (a paid subscription online scuba magazine of sorts) has
a free public access review on it from 2014. When you're ready, seems like it would tick some of the right boxes for oceanic, good viz., warm the right time of year, close enough to drive to & skip airfare, several dives, a short trip so you're not gone long, and hitting good reef diving in your area (in case 'home team' type offerings have any added attraction for you). It's deep diving so be aware.
I asked someone who'd worked that boat in the distant past the best time to go for a successful (i.e.: not likely to be blown out by bad weather) trip, and was told July 15 - Sept. 15. Be mindful the Gulf of Mexico is not the Caribbean Sea, and be aware how prone you are to sea sickness (& how to control it if a problem) before you go.
Richard.
