Being honest I don't want him on the show either. I think the card would turn out great if he isn't there.
The WWE has been fine without him since he retired from full time 3 years ago. Im not going to go on a bitchfest because I prefer not to have him on the card. Again it's Vince's company not mine. Im looking at the big picture here. He mostly will be working with Brock again. If he wins it's so what, he gets his win back that nobody will remember, unless Lesnar and Triple H tear the house down. Brock and Triple H don't have good chemistry together so they would really have to go all out on this one. If Triple H wins, what's the point, he's going to be written off TV after Wrestlemania. The same thing with Brock. If he wins, so what. If he loses, so what. He may stick around up til Extreme Rules, but the WWE would write him off TV again. On the flipside, Triple H isn't a roadblock in someone's push. So his presence doesn't hurt any up and comer or hot mid-carder.
People complain about newer talent not getting over, but what they mean is that their favourite isn't getting over, everyone else can go to hell. I'm for as many people getting over as possible, it would improve the show and the more over people there are, the more avenues there are to push new talent, yes, your favourites are more likely to get pushed if there are more over people to feud with.
I don't think he needs to be on the card. It's too late to work out a storyline of any sort for him vs an opponent, and since he's now the "COO", it wouldn't make much sense to have him be competing vs anyone nowadays, that's why he should stick with his backstage role.
Wouldn't of minded seeing Rock/HHH as a tribute to the attitude era match. Would of been awesome.
To be honest, if Austin were to ever come back for a final match it should be the triple threat that never happened. Rock vs HHH vs Austin. You don't need a complex story. Just make it about bragging rights and let it be the retirement/end for all three. Best way to end the Era, in my opinion.