Seeing as though your bumpers are already made for no body lift, I would keep it off and go for a full tub if I were you rather than have gaps. You truck is clean and I agree about it not looking as good.
I clearanced my front already for when I was running 305/70/16s without a body lift so I shouldn't have to pound too much more to fit 35s with my body lift. I know it's doable to run 35s and a 1" BL without tubbing because I've seen it done in person. It just takes removing the electronics behind the kick panels, pounding the firewall area in with a BFH and putting the wiring back in place afterwards.
I got the CBI after the BL so it was made for it. I ended up adapting my ARB by drilling new holes. I'm not sure if you can do that with the Shockworks, but maybe.? Even if you can though, I think trying to get rid of the gap you'll have with the CBI or living with it are both worse options than just tubbing the thing and leaving the BL off.
You will probably need to cut the front of the CBI to run 35s with or without the body lift (where the back of the rear tires make contact). I know I will have to soon when my tires get here. Or you can put in some bigger bump stops, but it will limit your travel. I have a couple more inches of droop in the rear because I'm running home made links with heim joints, but even with stock arms, I think 35s will rub the CBI.
You may have to trim the rear fenders a little too if you don't put the BL on. You'll be ok with it. Either way it will be a fair amount of work, but I personally wouldn't dig the bumper gaps.