Hope you're right but for now, all the signs are for HHH/Lesnar 2 and Rock/Cena 2, and if they want another "Once in a LifeTime/End of an Era" slogan, they can call it "How to destroy our biggest money show ever and make it the most wasted card of all time". They can write a book about it. Maybe in Bryan Alvarez's future book "The Death of WWE", we will get a chapter on WM29.
I think Taker is working WM, I don't see him missing a big show like that, it's just a one match effort and even with all his pain, I'm sure he can go through it. But there's a bigger chance that he's working with Cena or Ryback than Lesnar at this point IMO. I also see no reason for HHH to actually retire in the near future, he can still perform and be a one match guy for a few more years. He's there backstage anyway, when it's the right situation, he can always come back for a WM or a Summerslam. Don't see a reason for them to put the "retired" tag on him. Not to mention that I always hated this stupid "official retirement" concept. Anyway, what I see happening is Lesnar teasing HHH for weeks, saying that he retired because of him etc. HHH selling desperation on how he can't do it. Long story short, HHH agrees to the match, Lesnar dominates him, HHH brings Floyd, HHH going over at WM. Unfortunately, that's the pointless scenario I can see them doing this year. It can always change with one conversation but as of now, with the way they did things with HHH's "retirement", Lesnar/HHH is 90% the way I see it.
All the signs are definitely pointing to Rock/Cena II. There are NO signs pointing to HHH/Lesnar though, not to me anyways. Taker's matches have become the main thing they book in advance at Mania. Taker isn't working with Ryback. There's simply not even the slightest chance of it happening. It's Lesnar, Cena or bust as far as he's concerned. I truly believe Taker/Cena is for Mania 30 so that leaves Lesnar while he's here. If Taker can't work a match, then the most likely scenario is HHH/Lesnar but only then. Given the story arc that has developed over the past few years with the streak matches, Taker facing Lesnar makes perfect sense and I definitely think that's where we are headed.
As for HHH, he isn't going to be wrestling forever. All you have to do is listen to him talk about it himself. They have officially started the marking of HHH's possible retirement with the Brock match. Considering the fact that he has about 1 or 2 matches a year now, it's easy for them to go keep that going for another 2 years or so. I just don't see HHH/Lesnar happening at all, even with Mayweather being involved and that isn't even confirmed. Again, just because he talked about it doesn't mean it's happening.