Ideally all finishes should be the same or similar.

Not exactly know the meaning of your question, but here's i understand your question, Does tub/shower faucet need to match vanity faucet? Answer = yes and no. Depends on style of bathroom. Do you have a wet room? If you do then all fixtures should match in color IMO

Brushed nickel faucets will go pretty well with the ORB handles on the cabinet if done right. I would do ORB on the towel bars as well to tie in the look. If you really want a shiny chrome look for the faucet AND towel bars, then change the cabinet hardware. If the cabinet doors are dark, you could probably leave them.