That needs to be redone completely. Messed up!!

cover the pipes with a bulkhead, but then put a corner cabinet below it so it Looks intentional??

You can put a soffit above and retrofit a kitchen cabinet around the side pipes. No biggie.

Hard to tell from the photos, but what are the black spots on the large waste pipe and wall - mold? And the brown/tan discoloration near the one horizontal joint on the smaller pipe?

Is that some kind of wire run amongst the pipes? Do you know what it's for? Maybe secure it better?

Make sure you don't have any issues there while all this is exposed and accessible.

The kitchen design was intended for open shelving. We will put soffit around ceiling to hide those pipes. The issue is the pipes on the wall. How do I deal with that.