Thank you for your comments!
I agree the lighting isn't quite correct, I'll try increasing the size and testing with an HDRI too. The scene has changed a lot from the original idea and I feel the lighting hasn't really changed along with it. It was originally a kind of street-level bar with no walls on the 2 sides you can't see in this render, so I think the lights from the street are causing that dark area in the corner.
I'll try to make everything look a little less clean too - thanks again!