RE: How much pressure = too much pressure?
Ooo . . . sounds like the deer have already started being pushed out.
I didn't say this before, but your question/dilema is tough to answer. On the one hand you want to "leave nature alone", so as to continue the propogation of the species. But on the other hand, you hunt. There will always be deer. They survive. Move. But always survive. I still say enjoy your hunting experience while it still exists.
Tough one though.
When I was guiding, we were prohibited to let a client take anything less than a certain score or WE would be monitarily punished. So there would always be a good crop for next season. We also had to take a few rag horns and does/cows each year to keep that part of the equation balanced.
I sense from the fact that you are even asking this question that you must have a strong hunting ethic. So let your consience be your guide.