I think the bathroom looks lovely...mixing finishes is fine....chrome and brushed nickel is very common and mixes very nice together...I would leave the vanity but change the countertop...add one long counter tops that covers both vanities and have custom drawers added between them instead of a medicine cabinet.

You could frame the mirrors if you want..the lights for your vanity seem uneven, though they are centered on the mirror I think that's because the lowered counter. I have the lowered counter as well and I find it useless..whenever I do apply make-up, I never sit down. Here is an example very similar to yours, but with framed mirrors here is one that has a smaller vanity, but all at the same level..It has two lights and looks more balanced this is something completely different..looks like separate vanity used for make-up even though it's part of the same vanity..

IMO a lot of backlit mirror and honestly not a good source of light for makeup inless all LEDs in daylight bulbs so 4000K and not more since then you will get a blue cast happening. I sure hate walking through the bathroom to get to the closet . You will still need some overhead lighting to balance the back lits and give good all over light .

Yes, my original thought was a nearly continuous mirror but the glass folks actually said, “we sell glass for a living but in your case more mirror isn’t necessarily what is called for”. Lol. They were very nice about it. So that got me thinking a bit more about the function of the space. We need more storage and lighting.