Mine uses Spectacle Island, but he spends more time building ridiculously large buildings for personal use more than anything else. To date he has build a giant pyramid, a tree house, the house from Up, and is now working on his biggest project a resort Castle. He is also thinking about Noah's Ark and a bender statue that is laying down.

This for the same reasons (but my companions are at different locations depending on the companion). My ally is all ghouls, mostly in tattered rags, with the doctor in a lab coat with fashionable glasses so I can find her easy (she refuses to stay at her shop stand). Only 12 ghouls inhabiting the place since they all spawn in a tiny area and it looks a bit ridiculous. I might be kicking a few more out, although sending them to shops and defense posts helps a bit.

I really want to build on the bridges over graygarden (just realized you can actually build up there) so I might do that in the next play through.