It does halls-and-rooms in, uh. Kor'Pul, OF, N-whatever's Lair. Lake of Nur, yeek starting zones. Dreadfell, rhaloren camp, High Peak. It sorta' does it in Daikara and Tempest peak. Dark Crypt (but not shadow!). Lower bits of the halfling ruins. The rest of them use something else.
Sandworm Lair (It's what finally taught me to either read the te4_log.txt for artifacts or just not try to fully explore everything!), Trollmire (and by extension, the S-whatever Fens), and Maze are probably the worst of it for full exploration. Reknor (either version) is not terribly pleasant, either, nor is the Elven Ruins (Shadow crypt, trapped! quest). I guess the abashed expanse might be kinda' annoying to full explore, mostly due to the things attacking you.
Most everything else is quite easy to navigate and fully explore if you actually want to, especially the latter bit of that, as they tend to be pretty open.
I'm definitely glad T4 is experimenting with non-standard level generation, though. Halls and rooms gets bloody
boring when you've done it nth million (okay, so maybe I've only buggered about halls-and-rooms a few hundred thousand times playing roguelikes. Point stands!) times. Plus different battlefields force you to think and use new and non-standard tactics. I'd say that's a pretty good thing, all around.
Plus some of them are kinda' pretty. I really like the aesthetics of the heart of the gloom, actually. Makes me feel like I'm in a tree.
Edit: Fuller explanation of how-to-choose-golem:
Or hit F2 (F3, or higher, if you've got other allies), or click on its box in the party members area (on the left), or hit ctrl+tab. In windows, anyway, by default. You can change the keybindings, of course -- the list's under 'party'.
You can then equip it as you would yourself. This is also necessary to allocate the golem's stat and talent points.
The thing that was being noticed was refit golem. It pulls up a dialogue
when your golem is at full health, among which is options to change equipment. This function is mentioned in the description of the talent. It's also how you, once/if you get gem golem, insert gems into your golem's eyesockets. Last -- but not least! -- there's also an option to rename your golem. I always name mine, "The Loneliest Number."