Brock Return

Is WWE blowing the proverbial wad by having the Cena-Lesnar match already?  Having the confrontation makes sense: Brock returning by interrupting and calling out the 'top guy' in the company.  Honestly, I think they should have Brock put Cena on the shelf for a few months, so Lesnar can dominate in his absence and ol' John can return as 'last man standing'.  Character-wise, it seems sensible to have Brock tear through everyone until Cena was the last guy to represent WWE.  Brock can win both world titles and claim complete dominance.  Then, when Cena returns, but fails too, The Rock can come back and be The Guy who redeems the WWE lockeroom.  If they are slow-burning toward a Cena-Rock rematch, and/or a Cena heel-turn, that could be a pretty sweet catalyst: not only did he lose clean to Rocky at this year's Wrestlemania, but the part-time Rocky had to return to pick up John's slack.
I understand that Brock is only signed for a certain number of shows and they want to keep the momentum/money going (in this case, but not in Daniel Bryan's?  That is another topic), but where do you go from here?  Cena can't win at 'Extreme Rulez' because why would you have Brock lose his first PPV match back?  That leaves only a Lesnar win or some kind of schmozz ending.  Cena doing a very high-profile job a month after his highest profile loss to a part-timer makes sense if the losing streak is building toward Cena's heel turn I guess, but as a one-off job, John is on quite a losing trend to part-time guys.  Also, shouldn't Cena be the LAST guy Brock destroys, not the first?  (Basically, what Austin said back in 2002). I only say this because, once Lesnar has beaten Super-Cena in his first match, what makes it as appealing to see him beat Sheamus, Punk, Orton, et al?  In storyline terms, it seems like Cena should be the last hurdle for Lesnar and the 'last hope' for the WWE roster.
The ONLY way I can see them going is if The Rock returns at 'Extreme Rulez' to lay out Lesnar and allow a cheap Cena win.  That could lead to Brock going recruiting (Batista?) and setting up a Lesnar/??? vs. Rock/Cena tag match at the next PPV.  It just seems curious that Brock-Cena would make the most sense right now, unless it is for John to get obliterated clean again and have him go on the shelf to do 'soul-searching' and come back as a more edgy bad-ass babyface.

I think that they are going way too early with Brock-Cena.  Punk-Jericho and Sheamus-Bryan would have been enough to carry Extreme Rematches to its usual 100K buys, and Brock isn't moving the needle on a C-level PPV.  It's insanity to think he will.  

That being said, I think they do the shmozziest shmozz that ever shmozzed there, big double DQ, both guys give the ref their finisher, they brawl into the crowd and into a city bus and end up in the baseball stadium or something hitting each other with bats, whatever.  The worst thing they can do is have Brock just be another guy doing worked pro wrestling matches with a pro wrestler, because they'll kill him off faster than you can say "Lord Tensai".  The buildup to Brock-Cena has been enjoyable thus far, but every week Brock is on the show is another week where he just becomes another guy, like what happened with the Rock before Wrestlemania.