I became PADI certified just a couple days ago. did all my pool and OW training in the keys. I can't compare it to other locations but the keys had everything that was needed. a lot of dive shops (locally as well as divers direct) I bought and wore a 3mm farmer john bottom, and a 3mm EVO long sleeve top. it was plenty for all the dives we did. I'm a thin guy at 5'10" and 155lbs+-. I did use 3mm booties with my fins, but no hood or anything else. air temp was in the mid 70's with the "nicer" days in the high 70's. the seas didn't cooperate with us for a boat dive until tues afternoon with supposed 3-5ft seas (ended up 2-4s.) so the first three OW dives were done in a secluded lagoon (Jules Undersea Lodge) its 30ish feet deep and was 69 degrees when we went, so I had a very thin spandex type material shirt I put on under my wet suit. this did just find.
two tank dive from a boat, 30min drive, 30ish feet to some awesome ledge reef's with great visibility.
They Keys would be a great place for you to finish up your cert, I feel!