Therefore, if PvP is ever to work its way into D3, then it must maintain individual character identity while staying balanced.
A Diablo 3 MOBA/tower defense could be a good way of integrating both of these elements, and considering the unveiling of HotS, Blizzard looks agreeable to this mode of play. (http://en.wikipedia.org/wiki/Defense_of_the_Ancients) for those of you who are not familiar with the particular aspects of this game-type.
The main idea is then: level your PvE character in-game, earn your currently equipped skills/gears as you fight, and ultimately destroy the enemy base
To maintain individual character identity, each team could be comprised of five players who would be able to select from their bank of playable characters--these characters would begin at level one and would be able to select one primary skill to use/enhance every level (up to 10; earn 6 skills and then enhance them with four more skill-points). Their armor and weapons found in PvE (or bought off AH) would be accessible at the in-game store, to be bought with gold earned from killing their opponents, much like current MOBAs (except, you'd be buying your own gear and weapons from your stash to equip/trade[?] within the battleground). Like HotS, the games could be short (20 min). This might be a good way to diversify end-game, especially with a tiered ranking system of PvPers.
Balance would be more or less intact, especially at early levels when everyone lacks their current PvE gears. Only by killing the enemy/minion-waves/towers could you unlock your godly equipment/higher and more powerful skills.
I like D3, and I like the concept of DotA--could these game types coexist, or has HotS already done this?