I could have sworn Yoshida said he wanted to put in another mage class before considering more war classes. Let me find the quote....

Here:

If you look at the game right now, the balance is more toward physical attack classes with very few caster classes. Looking at MMOs, we realize that this is not a good balance to have, so the first thing that we're going to be doing after introducing the job system is probably introduce another caster class because that's what the game needs. We realize that currently, the game is lacking in a lot of crowd control type of spells, and we need these to make battles more strategic. To introduce these types of spells, we think one obvious way is to introduce a new caster class that's able to handle them.
Source: http://massively.joystiq.com/2011/10...naoki-yoshida/