You've received recommendations on the DiveOps I'd go with.
So here is some more things to consider.
As new divers, if you want to dive any of the deep wrecks, you will either need to be AOW certified, or *maybe* show proof of similar dive profiles in the past year, or hire a DM to dive with you. Most Ops will NOT put newish OW certified on deep wrecks, and with good reason.
As new divers, you may suck air. If you think that is the case, go with an Op that can rent you AL100's, or steel 100's.
Depending upon where you stay, find advice on where to eat. My favorite is the Fish House, but there is a lot of good food in the Keys.
If you are not aware of this, you will need a rental car.
As new divers, big crowds won't really impact your diving, but you may impact theirs.
Big boats are more comfortable, and easier for new divers IMO. Six packs are over-rated, and MUCH less comfortable especially if they are full. If you tend to get sea sick, stick with a larger boat. I guess my main point here is don't assume that you need a six pack to have a good dive trip.
Good Luck and have fun.