There's no real problem with paying for additional content. It's all a matter of how it's priced and delivered, though.
If this game existed as the only Digital game out there, this model would work well! But it's like... they DO know we've moved on to other stuff by this point, right? They DO know that having a web of DLC makes the game look less appealing to late adopters in some ways, correct?
If they released all current DLC as 1 pack at, say, 800 pts, or 2 packs at 400 each, I doubt there's be as many issues. Or even if they gave away part of it for free, and made you pay for the rest. But they currently want you to play 21 dollars (1680 MSP) for 4 characters, 10 songs, and 1 stage; more money for less than what was contained in the release game. There's little rhyme or reason to this release set, other than pairing related characters together by release dates.
This doesn't make me hate DLC itself any (more content for games I enjoy will always be good), but this does make me a bit sad at how poorly Japanese companies handle the content. Mostly involving SquareEnix, NamcoBandai, and Konami here.
Maybe they like the illusion of "choice" that such pieces give. Maybe it's all based off sales for things like Idolm@ster... But for a western audience, I think we're more interested in percieved value, and convenience.
And I don't think the lack of title updates means much of anything with this game, all of the DLC is appropiate in size, and things you don't own, simply don't show up in your game (like with characters being replaced with Grey Axe armor.)
It's a shame, the main person I expected to play this game with STILL hadn't gotten the game (life issues, other games coming out, etc), and the other person I play this with... shares a 360 with me, so we can't even play it together! Argh.
Other than MNC, this was easily my favorite SOA game, but they're really handling the post-release content quite poorly.