"When I first got into the water, I thought I was going to go into shock when the frigid water first raced up my spine (you know, when it first gets into your wetsuit?) "
That’s why I wear the hooded vest, it’s between you and that rear zipper and eases the shock! :)
As for your comfort level in a 7 mil, when I was young and ........ I did one ice dive in a wet suite, just one!
Late August, September and into October are our best times. The Gulf Stream has swept up tropicals to add a little color to the local fish population. Surface temps will be 70+ and I’ll do the inlets in a 3 mil but then because of out going tides your dive is shorter so you are out before the chill sets in. Beach dives can also be done in a 3 mil. Those same monthes are also the worst for getting your dive blown out by thunderstorms and passing tropical storms :(