They need to build up Brock and HHH more, the fact that Paul Heyman is doing all of Lesnar's bidding isn't adding serious heat to the feud. Lesnar will go over HHH, that has to be a given surely? You can't bring back Brock to lose both his matches, that would be asinine by the writers. For Lesnar to get more heat, he should invade the show and take out guys left, right and centre in the build-up to SummerSlam. Literally jump over the barricade and F5 guys like no tomorrow. He has to look dominant and dirty, with the great Paul Heyman on his side the heat could be enormous.
I think they'll go with Brock v Rock II at WrestleMania and Undertaker v Cena for 21-0.