Personally? I would paint the bumpers to match the fenders.
I really like having my fenders and cladding black, but for some reason I like the topaz with the green. It will look sweet if you go all black and I went Duplicolor gloss black.
I used plasti dip as my base coat. Allowed me to retain my stock paint job and its a great primer. I've had no issues yet with it and can go back to stock anytime. 3 coats plasti dip and 3 coats Duplicolor gloss black.