Something I was doing for BMS awhile back.

Did the original HL level have a huge transformer in the ceiling?

It has potential. As you said it could use some work on the textures and especially try to get in some variation with either decals, more textures or other details on the walls.

I do think it looks good, there are some thing you should tweak. I am not that good of a texture artist my self, but you could use some variation in the metal. Even if you brokw it up bottom part concrete and the top part metal, it could work. I do like how you used a transformer to do that, pretty cool idea.

Not bad. Lighting needs a lot of work imo

Quote from Minotauro

Not bad. Lighting needs a lot of work imo

Looks interesting as a map.

The lighting needs more work and the architecture perhaps in some parts of the map. Try to add more sprites for example to the generator.