Hmm, personally I think anywhere with renewable energy, so anywhere that can be near sea level or above (so solar panels are efficient) or anywhere near a thermal vent. I tend to build a large base in the shallows to act as a hub, then build smaller ones near thermal vents in far-off biomes. Typically that would be one seabase in the mushroom caverns, another in a cave under the big mountain, one in the koosh...all with thermal plants and a moon pool so that the seamoth can be recharged.

this looks prty sick, where do u think is the best place to build a seabase?

The new view from my new sofa