Almost all of the WordPress themes I use these days are of the "toolbox" variety. . . instead of having a strong built-in design that dictates the look and feel of the site unless you override things, they just give you an awesome set of tools so you can do whatever you want.

GymBase is the opposite of that approach, which I don't do much anymore, but which I still think is the right call for this very specific client/application. The design is solid and has aged well, I think, but the most valuable thing for the particular health club I build this site for is the awesome integrated Schedule/Classes/Trainers feature. Being able to enter data into each of those three tables( Class Info, Day/Time, Instructor Info), then tie them all together so the screens flow seamlessly from one kind of display to another and show useful links/excerpts where appropriate--that is well worth the lack of flexibility you get from a theme that's highly customized out of the box. This would take a LOT of work to do from scratch using any of the badass build-it-yourself themes I usually work with, and it's a real value add for both the club and the site visitors.

I'd also add that the paid support is affordable, responsive, and effective. I had an annoying problem that stemmed from clients not performing updates regularly and some key elements being hopelessly out of date. . . they walked me through a nonroutine update pretty painlessly to get them back on track.