Reality Check
Keepin' it 100
I don't mind the Cena rematch mainly because I'm curious to see what they're thinking going forward which is a nice position to be in for once with his character.
I know he just lost to Bray but. .. If he hadn't come and gone so many times Jericho since he's leaving soon would be an expendable big name scalp to keep Brock busy while Cena "rested up and saves Jericho from a post match attack". Fans care about Chris still and him losing in devastating fashion wouldn't hurt his legacy/ standing in any way. A simple Heyman and Brock laughing at him and referring to him as a has been in the midst of a midlife crisis on the highlight reel (I like Jericho and don't think this but it could easily be a talking point) would give Jericho reason to pick a fight and Brock being Brock would have no problem in wanting to beat up "a has been having a mid life crisis"
I was thinking Jericho or even RVD given his history with Heyman. Both names carry weight and both won't be harmed by losing to Brock.

Lesnar ain't working 4 PPVs in a row