I need C&C!!!!

these are two renders for a small horizontal condo I'm working in.

In the interior one, I don't like the borders oh the sun's highlights, i'd like them to be sharper, without that grainy look. Inly I don't know how to do that. Also, the material in the left wall is some kind of red tezontle stone squares very used in mexican colonial architecture (like the ones in the attached photo).

I spent a night making that procedural material but I did not like very much the results. If you wish send me your e-mail and I'll send you the procedurals so you can see how did I make them.
The ideal material for the seats could be some black leather, any idea on how to make it?

About the exterior one, say anithing you think I could do to make it better...

I can't post the images directly in the thread ... suggestions please?

you're saying CG sunlight is actually based on a real thing????