Most of my stuff is teen, so it's pretty easy to switch to non sexually explicit thumbs.
Other than that I have a movie site or two, that require hardcore content. One site was new and I'm changing it to a general babes style TGP with compliant thumbs. The other is a larger site and is getting redesigned as I type. It will still have thumbs but any hardcore stuff will be text links. So it will be the best of both worlds.
I don't think I'd even try to attempt to turn a established full thumb site into 100% text. I think you would suffer a big traffic loss.