Have you even read my previous posts? I already said that I think that DMC4 destroyed the picture and makes no sense whatsoever :/
The rest is sorta fine, not the best character development, but it can be seen.
Look, you have DMC3, where Dante starts out as an immature brat, but during the course of the game, he matures, not all that much, but you can see a change; give him a few more years, and it's quite natural for him to become DMC1Dante.
DMC2 again takes place several years after DMC1, so DMC1Dante developing into DMC2 is quite possible; as I already said, by the time of DMC2, he's been through a lot, maybe lost even more of the persons dear to him, I'd say that hardens and matures a person greatly.
So, there is character development, Capcom just made the great mistake to not show it on-screen, for the most part.