Re: In all due to respect for Undertaker, retiring would be the best option for him.
Oh, I love Undertaker and will be very sad to see him go, but I agree that it's about time. I remember several years ago thinking that he'd probably win a clean 20 at WM and then hang it up. Obviously we're way past that, but at that time I remember telling friends that if he has to lose, I hope it's to a young up-and-comer that will be put over in a big way... Well, obviously that didn't happen, and quite honestly, it wouldn't have mattered anyway.
Several years later I see that WWE would have done nothing with whatever up-and-comer that may be. Now, I just think it needs to be a marquee match, and hopefully whoever goes over can then put someone else over in a few years when MAYBE WWE will have it together. I'd like to see Cena retire him at Mania, then maybe do a final heel run. Maybe, just maybe, when it's time for Cena to hang it up in a few years, WWE will have the it together to the point of putting a young talent over him.