I think there are more than enough places to hunt...
I think there are more than enough spawns everywhere to hunt without overcrowding... and even if there is overcrowding, big deal... just team up and hunt that way.
In you example about uber hunting next to n00b, n00b should be happy to be there, and just stop wasting ammo and enjoy the uber giving him free evade, or if he runs around in circles, athletics. If nothing else, in situations like that, n00b could get tons of mob to chase him, die, chase him, die, etc. and sort of make a parade of mob and lead them all to one place, causing them to overtake the uber... then in mean time as uber dies and gets frustrated eventually, n00b goes and hunts in the now less dense areas that he drove a lot of mobs from but where new ones are showing up since uber's killing, causing re-spawns back where n00b is.
It's a cyclical thing - the loot pool is.