Calypso is directly across from Pier Park, which is grand central for shopping and has many dining options...several of which have outdoor dining and a couple of which have gulf views.

Calypso is a big place, but has quite a bit of beach as well and in May, I don't think you'd find it overly crowded. The only negative to Calypso in my opinion is there are no hot tubs, but that may not be a factor for you.

If that is an issue, Aqua is just two (or so) doors down from there and is also walkable to Pier Park, although a little farther than Calypso. Both places are very nice and newer. We use VRBO.com to rent directly from owners and get better rates.

Have a good trip!