Although I agree with the fact that humanoid Bionicles are getting old (or, atleast they have been for the last 2 years), I do think that Lego is not at fault here. Ok, they missed a few gaps. They can't fix it without making new moulds, destroying the humanoid aspect of Bionicle, or making the price go up a dollar or two to pay for the moulds and plastic. Generally speaking, Lego can't help those gaps. They don't want complex fillers for them, because that could stop some people from buying them.
However, I agree with your points. The unique Toa and Barraki are here now, but what about Titans? Are we going to keep alternating between unique canister sets and unique Titans? I hope not, because I am not going to be buying $60-$70 of sets that look almost completely the same. The ONLY reason I would buy even one is for pieces.
Oh, I hope Lego makes unique Titans as well, or the world is doomed.
-Deep-Freeze