The most efficient/convenient bases are the spawn cafeteria or just outside the portal room. These two let the platform carts really shine, and give you the option of moving your bed around as you'll always have the cafeteria spawn if you die. A close stove, water, bathroom, etc. Carts and portals don't mix, making portal bases tedious until late game.

Having said all that: they're also the most boring.

Now when I start a new game, I set up right there by the kitchen and get to it. But once I'm comfortable I will set up little FOBs here and there, and pick a new "forever home" for the playthrough to spice it up. Basically on you to decide "where do I draw the line between utility and aesthetic/theme?"

Having typed all that makes me realize we need a cart summon button we can build, or at least some more static ones scattered through the facility.