I think the special items acquired from bundles (and, ideally, even from booster packs as well) should function similar to the Heirlooms in World of Warcraft. Seriously, the only real reason I refuse to buy one before my character hits level cap is because I wouldn't be able to benefit from the best power tier of the items before then, and to my understanding once you choose the item level it cannot be changed. If the item instead simply matched the character's tier, increasing it's own power every 5 or 10 levels or whatever, then suddenly I'd be yes, sign me up for a bundle.
I agree. Bundle gear should evolve with the player level. It should work both ways too. If you pass the gear from lvl 90 to a lvl 20, it should drop down. This would give a lot more flexibilty to players and give more incentive to buy new bundles as they come out. No need to choose a level, just have it chosen by the level of the player equipping it.
I have quite a bit of bundle gear I have never redeemed. I would have no problem redeeming it if it could evolve with me. I would pay crowns to make that "evolving" process happen if I could.