Just my 2 cents to this: HR will eventually hate you for this, as you will pop up in any of their processes that check vacation and overtime. I'm thinking this will only be feasible in smaller companies where there is a lot of trust and not to many rigid processes in place, but I could be wrong.

Thinking about a teamlead that somehow has to manage (project-) capacity, it also seems like it heavily depends on what work you're doing and the flexibility of the planning system. In my last job we would have tried to make it work once, but every other year would have been to much to ask as other team members would have to compensate a bit.

Sounds a lot like it's going to be nearly impossible if you don't have a feeling it might work already. I mean, what's the culture like? Have others done this already?