XMR has been almost the only alt I've found to have any theoretical value over the years. But I'm gonna push on this Zerocoin thing:
List of possible pitfalls wrt ZeroCash/ZeroCoin:
-If ZeroCash/ZeroCoin is launched on behalf of a company, which seems the case here, the company can be given a gag order (e.g. to add a line of malicious code).
My understanding is that it's fully open-source. So...?
-If I recall correctly, the creator of the genesis block holds some kind of masterkey. As a result, you have to trust this person. Even if this key was held by a group, you still have to trust that particular group. In addition, you have to trust the program they run to create the Genesis block (the masterkey could be in there).
As I recall, this is being addressed by an alg which proves that if only ONE person in the group destroyed their key, the seed is secure... If done right (big enough group, including entities like EFF, etc) I'm guessing the market will find this sufficient.
-It's too opaque in my opinion. If a bug existed that would create additional coins, there is no way you would see it.
This is the criticism I think is most valid. I haven't heard a decent counter-argument yet. Anyone have one? Zerocoin *did* say the system will basically support a viewkey-type concept, so maybe there's some way using that capability to prove total supply? Dunno....taking shots in the dark here. If there's no solution to this, I think it's a critical issue with Zerocoin.
-The math and cryptography backing it isn't peer reviewed yet and in an infancy stage.
Fair, but I doubt that's going to matter all that much to people, assuming it gets even just a few months of successful operation under its belt.