Adding fiberglass batts on top of cellulose; should I remove some cellulose?
I would not sweat it. The amount of compression versus what it would take to remove the 1" of cellulose, with all the wires, unseen framing blocks, and whatever else is concealed, to me is not worth it. 

Usually what I am used to seeing in attics is insulation heaped up in places and thinner in others. I would take a push broom and pull or push the high spots and move them into the low spots, then add the fiberglass batts.