My family and I love 30A. We've gone about 4 or 5 times. Once for Spring Break, a few times for Thanksgiving (if the Ags were playing in Baton Rouge or Austin) and for Christmas/New Years.
You get a price break going in fall and winter as it isn't obviously as crowded. We lucked out for our Spring Break trip as Texas break was a different week than Georgia's. Apparently it gets super busy and authorities had to put in a curfew due to rowdy kids.
We've always rented a VRBO and split the beach house among 2 or 3 families. We've stayed in Seaside and Rosemary Beach. Both are great. If you're in Seaside you should definitely rent a golf cart as you can drive up and down most of 30A until you get to Aly's Beach. If in Rosemary, you are not allowed a golf cart, but it is beautiful and very walkable. It's also probably the largest of the small beach towns along 30A.
We always fly into Panama City/Northwest florida beaches as our destinations are on the southside of 30a. Its a super easy flight. Southwest has direct out of hobby.
Let me know if you have any specific questions and I'll try to answer if I can.