When I scouted out a location for a Plains base, I wanted one that was far from any Fuling village, not near any Deathsquito or Lox spawn points and not too far from Black Forest/Swamp biomes.
I settled on this...
https://steamcommunity.com/sharedfiles/filedetails/?id=2426221264
The local Fulings, Lox and Deathsquitos take care of any invasions, so that is never a concern.
The only minor concern is the nightly Fuling patrols, but even they can be ignored because they cannot do any serious damage to my stone walls. Any damage they may do to my fields, fences or mills is easily repaired the following day. So, I ignore the night patrols and go to bed or hop through my portal to get on with stuff in another part of the world.
It may seem an odd thing to say, but I've found this base in the Plains of all places to be the least troublesome of any biome LOL.