I've got about 30 bases in Meadows and Black Forest, many of them adjacent to other biomes. I try and equip them all the same with maxed Bronze Age utilities, boar farm, wolf farm, crops. I pretty much gather up everything, shoot anything, etc. like an obsessive hoarder. It's noticeable that the item and creature spawn density and frequency vary quite a bit within the same biomes. For example, seagulls are thick as flies on one coastal Meadows base while another one has a painfully low population. Same goes for pretty much everything else.
Since I haven't gone past Bronze Age I can't comment on iron, silver, etc.
To me I like the variability as it makes you move around and not just camp.