I have a few large prints (42x42cm) I've made recently that I want to frame for display (gallery and/or home).

It's been a while since I've shown any of my work publicly, and I'm a bit out of the loop as far as current aesthetics goes. Is there any standard or certain look or approach that's common and recommended?

The two prints in question are both very low key, taken at sunset after the sun went down and at night with only artificial light, and I'm concerned that a clean, crisp white matte will only serve to make them seem darker and possibly reduce apparent detail. Would a 18% neutral grey matte still look professional? Or could I go completely crazy and choose something in a dark color that compliments each of the prints?

My second question relates to framing. Previously I just pointed at whatever frame I liked and that was that, I'm trying to be a bit more professional now. Are there any common methods or looks for gallery framing?

Thanks for any suggestions and advice.