Before 99 your chances of going 31%-0 are higher than below, so why would you take Undying Before End-game and not after (your end game choices are fine, I'm just getting a feel for your reasoning - I took Undying as well).
And if you are waiting out PvP until you get to end game level it's better to just take Savage for PvE and then pay to change them at 97+ (though I'd say end game is 99, but that's just my opinion). By then you should be seriously considering getting Wizard Spirit (if kept Arcane Power), as well - just an aside.