VR Environment - Roman Domus (lighting assistance)

Hey everyone, I was hoping to get some C&C on this environment I have been spending some time on. At this point, I’m feeling stuck on how I can improve the look of the scene, but I know that it could use a lot of changes.
I think the biggest issue is with the lighting, if anyone could offer advice on how I could improve it, I’d appreciate any help! Attached is a reference img showing what I aim to achieve and my current lightmass settings (note that lighting quality is set to high in these screenshots).