I think for the champion quests you don't have level matched champions for, the best bet is to pick one follower who counters the spec and is hopefully within a level or two of 110, which hopefully drives the success percent over zero, and then fill with your stronger recruit units instead of trying to counter the other traits.
I was able to push the rare heroic Halls of Valor mission last week to 100% using a level 109 champion, the 20% bonus to first mission of the day order hall trait, and two bands of trackers, IIRC. Between the bonus and two 30% disposable units, I only needed 20% from the countering champion. I have no idea if that still works, but if you're trying to do a mission and your guys are under leveled you'll probably get a higher success rate with filler recruits than all underpowered champions since filler recruits are just success chance buffs.