Edit: Thinking about it, there is a 3rd kind. Some people like AFK type bases. Bases with so many traps and so much redundancy, you just stand in it as bait and the traps do the rest. They would be fun to design and build, but in my opinion, a bit boring to play. I might try that once I feel I've squeezed everything out of my max XP base.
Heh, that would be me later stages. 60 dart traps. (15 rows, 2 on each end of the step), electric fences on each stair.
It works quite well, but yes, is rather boring. (you have to break it into 2 circuits, so for some fun, you can turn the front half off,
let the zed pop to the top, shoot some, then, when ya gotta reload, turn the front back ON. KZRRT! THWAP! THWAP!

)
Mind you, nothing seems to work fully on the vultures, so them ya gotsta shewt.
90,000 darts to feed it, so that's a ton of mining, not to mention all the steel that goes into the base itself.
(you can't really just afk, but can ignore everything except the vultures)
Tested on insane, 64 zeds per. SOLO! get several players going, and I expect they may get a few up the steps to the main landing. dunno.