The room is mostly fine but the ceiling and floor suffer emptiness. Maybe adding some trims, minor detail, floor variances, light sources and gradients will add more contrast to the room and therefore more depth. It feels very flat right now.

Also the platform textures get cutoff or actually repeat in a bad way. Custom texture is needed here.

I have found that a good way to make blank ceilings interesting is to add a glass ceiling skylight. It makes the room feel much more open and just looks better. It's what I did in my areas next to the water cavern.

Agreed!

Fixed