You were using 80 cf aluminum tanks in Bonaire, the standard around the world. Aldora's (and Living Underwater's) 120 cf steel tanks provide 50% more air so dives can last 50% longer, at least theoretically. If you start to get cold after an hour, maybe an hour is enough for you. Or you need a thicker wetsuit
But there's a difference between most Cozumel and Bonaire diving. In Bonaire, many of the shore dives start really shallow, in 5-10 feet of water there's already plenty of growth. They proceed to a wall that maxes out in most cases at 80-140 feet. (Two sets of walls in the southern sites if you swim out that far.) In Cozumel, on the other hand, the walls start out much further, hence the need for boats to get you there, and they start out deeper. The average depth of your average Cozumel dives will undoubtedly be deeper than the average depth of your average Bonaire dives, hence your air will not last as long. And, when boat diving, you're paying much more per dive than a Bonaire shore dive. So some of us like to pay a little more for bigger tanks that can allow us dives over an hour when we'd otherwise be limited to 45 minutes or so on an 80 cf tank because we're not the best with air consumption (my, cough, excuse is that I take macro photography and hence swim against the current more than non-macro divers to get my shots) or we like to dive deep (cough, no excuse). Others have perfectly wonderful air consumption, easily get 90 minutes on an 80 cf tank with plenty of room to spare, and love to brag about it while putting the rest of us down for something not doing something right. Those people suck
Oh yeah, forgot my point in my ramble. Yep, probably a good decision. Not that there are other decisions you could make that wouldn't be equally as good. Fact is, there are probably an unlimited combination of decisions that would all be good. Yes, you'll meet divers at Scubaclub and be able to socialize with them after hours. Or you could just meet people on any other dive boat and maybe end up hanging out after dives or hanging out at the bar or pool and meeting people, whatever. But I agree that Scubaclub would be a better guarantee of sociability. I've done a few solo trips there and it's hit or miss. Definitely miss if you stay at a hotel like the Bahia Suites where you have almost no venue for contact, definitely mostly-miss if you stay at a couples resort like Secrets where everyone else is part of a couple and you only socialize when they take pity on you being along, more of a hit at the Occidental Grand where there are groups of drunks willing and ready to adopt you as long as you drink just as much. But a dedicated dive resort like Scubaclub is the next best thing to doing a group trip, or maybe better since you're never obligated to stay with the group if you want some down time alone.
Since it's your first time there and you're only used to diving 80 cf tanks in Bonaire with shallower walls and little to no current, the group experience and larger boats of Scubaclub would also be a bonus to you, I suspect. And, going back to the theme of being solo, hopefully the dining will be more convivial, assuming they don't seat solo travelers at solo tables. When I travel solo, dining can often be the loneliest part of the trip, except for the sleeping alone part of course.
And going back to the theme of being a good decision, it's just that. There are combinations of decisions you could make that would almost ensure a lousy trip even for the most optimistic, especially as you're a first-timer there. At Scubaclub, you'll be guaranteed a decent dive op and decent companionship and supposedly the food is decent too. You could do far worse and it's not a certainty you could do much better, so your decision gets my thumbs up in case that means anything!
