Easy enough.
Under some draconian ruling, the Champ has to only defend once a month (the PPV).
Any other time, it's non-title or Punk doesn't fight on TV.
Keep him on Mondays (AKA, the "A" Show) so he only has to be on TV 3 times a month.
6 appearances officially with any House Show appearances set to a predictable match formula (Tag Matches would be great because you could pair him with someone to do all the work and then he'd tag in to do the finish to keep his heat), etc.
With RR out of the way, he'd just have to do Elimination Chamber (Maddox as ref maybe?), win that (maybe have him come out last versus a busted Cena or Ryback or Rock and get the quick finish there too?) and then roll into the program with Taker.
Streak versus Streak like you say with either Taker retiring as Champ or Punk getting the nod and becoming THE #1 Guy.
It's a LOT to ask and book and it'd really be up to Punk if he'd want to do it as it's a long schedule and while I wouldn't doubt his promo skills, eventually the crowd might gain X-Pac heat against him for never losing.