Clean Cut by MFX
Clean Cut is a modified idbase map that is small to medium both in overall level size and, for the most part, in scale. Its visual design is quite good, with effective texturing and lighting complemented by recurrent details like transparent windows (some broken), pipes, and vats or tanks of slime. There's also, of course, crates, and some machinery to move them. Overall this is a suitably detailed style, executed well. The whole level is indoors and the layout strikes me as rather arbitrary, but given the size of the map and the generally linear route, this still works. Perhaps the best comparison to this map is Scampsp1, although this is on a smaller scale.
I didn't really like the cramped scale of much of the level, although this did get mileage and a challenge out of base enemies without resorting to hordes or ambushes. Dogs were used well, such as in shot 2. You can't play carelessly, there is something of a challenge, but if you're good at Quake (ie better than me) you should be able to blast your way through without much trouble. Overall, there are lots of great base maps out there, and this isn't especially unique or ambitious, but I found it enjoyable, despite the reservations about claustrophobia.