Buy to play.
Then micro-transaction store with speed levellers and cosmetic items only.
That the best model right now for a large budget MMO. And what I would hope they have sense to do.
Pay to Play works if you can get a solid cult following (EVE) which Elder Scrolls could potently have, but the game needs to be made to budget ofr it to work.
Trying to make a big-budget MMO Pay to Play will not work any more (SWTOR good example) because people do not stick to single MMO's, they tend to play multiple Free to Plays. And having a Pay to Play makes it too expensive to spend more on there other MMO's. Hell even WoW is dying it's very slow death (though because it did so well it will take years yet, maybe even a decade).
Free to Play play can be great or it can be horrible. Bug it sucks for large budget MMO's because they can't ever guarantee they will get their money back, which makes publishers nervous to say the least.
If they limit micro-transaction's to speed levellers, faster unlocks and cosmetic items only. Then it tends to be OK the majority of the time, not always though, depends on pricing and these games tend to be cheap.
However when they lock content behind micro-transaction's (even though it's normally non-essential content or extra balanced items) this is when it starts to get horrible especially when they don't know how to price. (APB Reloaded for example its around £20 per gun to unlock each one account wide).
Of course some Free to Play MMO's lock content behind micro-transaction's and then give you an extremely slow way of gaining access to it, which works for a little while until you get sick of it (Star Trek Online for example has 75%+ of its ships locked content behind micro-transaction's but lets you buy store currency with in-game currency, but there are limits on how much in-game currency you can acquire each day).