I still maintain that "Pay to Win" only applies to PvP. If you're using paid powers to complete things faster, and get more items... well, for me, I don't care. Sure, you're "winning," but you're beating NPCs. Whereas in PvP, the whole conceit of that endeavor is that everyone starts on a level playing field gear wise, and skill / build choices / etc. allow you to defeat other players. If you pay for an item that allows you to easily defeat other people in PvP, that is the literal definition of paying to win.
The only time "Pay to Win" would be an issue in PvE is in the market, but I think it was amply demonstrated that you didn't need great drops or lots of drops to be a marketeer.
That's a sort of player-centric view of pay to win where the definition of "winning" is mostly congruent with "beating other players." But I think it fails to capture the sense that City of Heroes was a game, to distinguish it from an open sandbox, say. Many players took the position that the purpose of the "game" was to give the players whatever they wanted that the dev team could reasonably accomplish: that's why (although I'm not saying you're saying this per se) many players felt that increasing reward rates was something the devs only failed to do out of malice: since its trivial to simply increase those numbers, and takes no real effort on their parts, the only reason for not doing it is to punish or otherwise manipulate players.
But neither Cryptic nor Paragon viewed CoH in that way. As open as they tried to make the game in many ways, it was still something they considered an actual game with rules and reward systems and content structures that were about delivering a structured playing environment. Given that, there is a lot of validity to the statement that if the devs placed strong limits on most players, but allowed some of them to buy their way past those limits, that was a form of pay to win, in that it was a way to pay to break the rules. Not everyone thought the rules should even have been there in the first place, but that's not really relevant.
I tended to take the more moderate position that something became pay to win not just when it improved performance but did so in a way that significantly exceeded the normal design rules by a higher margin than non-exploitive non-purchased gameplay could accomplish. So in the case of Codewalker's example of using the store-bought team teleporter on DocQ, I think for me that's a grey area that comes very close to the line. It does significantly improve the rate at which you could earn merits, and if you were *fast enough in all respects* you could earn merits significantly faster than most other activities I could think of. There's definitely a pay to win aspect to that. But its not so much higher that I think its definitively pay to win, when combined with the fact that the *overall* reward rate for running a highly accelerated DocQ is still not outside the rate the standard game supported with non-exploitive reasonably optimal gameplay. I think quick-ITFs would, in the long run, meet or exceed fast-Q (not on pure merits, but overall) with less need for perfectly optimized gameplay. Since quick-ITFs could be run by any reasonably powerful team without the need for any purchased powers or marginally ultrahigh or ultrarare game rewards, that places fast-Q for me on the edge, but not necessarily obviously far over the edge.
Fast-Q is, however, a good illustration of how the eye should be kept on the overall prize - net overall reward earning rate - and not on overly specific gameplay elements (like critter defeat rate or offensive output) when deciding if something boosts players' ability to exceed what the game design intended in ways fundamental to the way the game rewards gameplay. Gameplay-rewarding game rewards are the way *the game* defines "winning" even if it doesn't call it that. That's the definition that I think should be the primary one when judging "pay to win."