Amazing build! I especially love the lobby ceiling design. One thing I’d add though to make the build stand out more is adding interior trims right below the ceiling - here for reference.
You could also inset the faces of the ceiling to create this sort of design or something similar
picture taken from a hotel somewhere in Manilla
These opinion of mine are purely just my preferences, and shouldn’t be taken anything other than suggestions to incorporate - here are some things I’ve picked up that could help with the build:
Lighting
In my opinion the colour scheme is spot on, I like how the colours blend and compliment each other. One thing to emphasize this a tad bit more is to add some atmosphere into your build.
There seems to be lack of shadow - evident from the hallway picture - and I feel this is either due to your lighting technology or your light composition is set too bright. I suggest configuring the light sources and just mess around till it’s at a lighter tone
You could also add some of these properties under Lighting to help create a more defined atmosphere of the build - I suggest adding ColorCorrection to lighten up the build, and atmosphere to create some sort of fog.
Here are some of photos of a showcase I’m working on, albeit not very much at the moment but with the use of these properties I am able to create this:
PBR Textures
The textures are alright and could use some work. Incorporating PBR Textures if you haven’t already would help create a somewhat realistic environment if that’s your intention.
Here are some sites I use for finding PBR Textures: https://3dtextures.me, Textures • Poly Haven, https://freepbr.com
Small Changes
A few things I’ve noticed is that most objects are floating. Evident from the first picture: the door frame, lamp, elevator buttons - I don’t know if this is your take on modernism but personally it looks awkward
The build overall seems a bit spacious for my personal liking, and I don’t know how it looks in game but you should just be wary of proportions and stuff like that - if there is by any chance a way to test this game I’m sure it’ll help open up for more feedback.
That being said though the build is looking splendid, please do not be afraid to take time with your projects and carefully skim over everything, every minute detail. The time factor adds up, the more love and dedication you put in something the better it’ll turn out!
Hopefully I said something in this jumbled mess that’s atleast somewhat useful 
I’ll be watching your progress with great interest,
thank you for your patience~!
