I certainly hope not. The current crop of MMOs doing FtP/Cash store I have no interest in. Even GW2 has lost all its lustre to me because of their heavy reliance on it. It is very difficult to do correctly, and most studios have no clue about it.
I don't mind FtP as a trial, but if I decide to play a game regularly, I find I would rather pay a monthly fee and have all content accessible for that price in-game.
Especially games that require money to unlock essential stuff, like more inventory space, or faster leveling, or removal of daily limits or in-game items that are crucial to advancement.
For example, Warframe has the Platinum system, where you buy Platinum for $$$. Two of the items, the Catalysts and Reactors, essentially double the power of your weapons and equipment. They are very incredibly rare. Or, of course, you can buy them for about $3.
Now, ever since they introduced the trading system, you can try to sell special tradeable gear, but most of it is so worthless, you might get 1-5 platinum out of a whole set of parts for one "prime" weapon unless the thing you're trying to sell is one of the few incredibly rare ones (they are rare because they almost never drop and they are not easy missions to acquire it from).
That's the kind of thing I hate in a F2P game. Or, games... I'm not sure what game it was I heard about this, but there was a game that was F2P that was coming out that limits how much XP you can gain in one day, unless of course you pay $$$ so you can gain more.
That's another kind of thing I hate in a game; the rate is usually set so low that by the time you actually get anywhere, all of the content that you're ready to do is long obsolete and nobody is doing it anymore and/or if the game has PvP, the gear you managed to collect has been made obsolete awhile ago and you're still just as ineffective as you were before.
F2P is not the sheer awesomeness everybody thinks it is. You trade full or near-full access in the case of games like WoW (just a few vanity items in the cash shop) for limited access, and a lot of times the limits are crippling and very difficult to actually enjoy the game without paying. Oh, sure, you could just pay a little here and there, but to be quite honest, if you're not "into" the game enough to care about the F2P limitations, then you're probably not "into" the game enough to actually see most of the content anyways, even if it weren't for the limits (hence why these kinds of people are not willing to pay the subscription fees).
IMO, the best way to do this, would be to set a monthly rate, but also scale it down to how much you actually play. For example, if the going rate for a game is $14 per month, we could say that 20+ hours per week avg costs the full $14.
If you only play 10 hours per week on average, you'd pay $9.
If you play 5 hours a week avg or less, you'd only pay $5 for that month.
And it'd scale per hour, so if you played, say, 22 hours in a month's payment period, that's 5.25 hours per week average, so maybe you'd pay $5.10 or something like that (there'd be a mathematical formula for this) for that month.
If you had some days off work the month after that, and you played 37 hours during that whole month, that'd be just over 9 hours per week average, so you might pay something like $8.75 (10/wk is $9) for that month.
And of course if you play 80 hours or more during the month, you pay the full $14.
That way, casual players wouldn't get screwed on subscription fees (which is where most of the anti-sub complaints come from), and the cap on the monthly fee means the no-lifers aren't paying exorbitant fees which would push them away either.
Win-win for everybody involved. Everybody gets full access (you could run a pure vanity cash shop for extra dough if you wanted), those who play less pay less, and they should be happy too.
