I'm in.
Just with the wait until 15 players are left, I don't think that's a good idea. If we decide to go for a random lynch in the first round, I'd prefer if that person could roleclaim so we can make sure that we're not lynching a cop or something, for example.
Instead, make it that for the first couple of days and nights, you can't role claim until you are half way to a hammer vote. After those few days, you can role claim any time you want.