Both are to small for that wall: is it possible to rotate the artwork and move to that wall and than put the three panels on the smaller wall?

I like the mirror better than the panels. Your chandelier seems a bit high - if you lower it slightly, it will reflect in the mirror better.

Love the art you have on the other wall.

For sure, move the large print to the other wall.

You definitely need to flip the 2 walls. Scale wise and also for focal point the artwork needs to go on the larger wall and the panels on the other wall. I wouldn't use the mirror (2 similar large scale shapes in the same space) the 3 panels would be more visually interesting. You can still use your sconces on either side of the artwork.

Pretty room :) It looks like your mirror is over a console...hard to see. If so, turn your mirror vertically. It will look lovely worth the sconces. Also I agree your beautiful chandelier should be a little lower.