Well, so far I'm working on finding a workable formula so that you don't need tons of items just to stand a chance of making your DCs at higher levels. I think I've got one, but I'm still debating eactly how low it should really be.

See, I'm of the opinion that the Amulet of the Silver Tongue should be a Ring of Wizardry for Truenamers, not a booster to allow for continued functioning of the class. The Law of Resistance will eventually make it so you you can't get off another use of a particular Utterance, but when should that be?

The other idea I've got kicking around is making personal truenames worth something. As is, it's a +2 DC to get a +2 bonus on getting through spell resistance (which you can just ignore by taking a +5 DC on your Truespeak check) and then you can also see and talk to that person using two class features. Not much for a couple thousand gp.

But I thought: What if an Utterance spoken using a personal truename has a much greater effect? Like instead of getting the Celestial template temporarily when someone used the Incarnation of Angels Utterance on you, you instead gain bonuses more akin to being Half-Celestial? So far, though, it isn't coming as well as I'd like. Some Utterances just don't suggest good boosting effects.