Im fine with the idea of MT in game. Just have the content available to all (but easier to get, get it earlier in the game, etc) for the MT items. That way if people want to save time, they can spend the money.
WKC does a good job of this. You can buy items for your Georama if you want, but you do not have too. (It just opens up different things earlier/makes it easier to buy certain items, etc)