Some awesome work dude, I've done a Paintover of a couple of my ideas which I think would add to the scene.
I think you need to break up some of the straight lines, if just with some colour. The yell tips on the base of the wall pillars, would break up some of the floor/wall lines as well as giving variety.
you could add a hint of a pillar on the right wall as well. given that the pillars are quite straight it seems odd that these pillars are only on 1 wall.
The small lights could have some emissive lighting, but also there's some wall sections without light, although this would be dull if everywhere I think you need to consider where these tiles are placed.
I'd suggest adding a few more points of interest to the scene, the plane on the wall could be a poster/propaganda/advert/game hint etc.
There's some alignment issues between some of the horizontal banding on the wall tiles towards the door at the top