Well, that's a possibility, although Moka isn't a Succubus, so I don't know, how that would help in this matter.
After all, Kurumu did THAT, so that she could use, her entering the dream / mind skill and somehow, help Tsukune in regaining his sanity.
I don't think that, it has been mentioned that vampires have a similar ability.
Although, that doesn't mean it won't happen, since it would be a pretty good way of balancing things out, within Tsukune's harem.
We will see, when the next chapter comes out.
As for Tsukune's transformation, becoming more complete - well, I would say that we already got some idea, on how strong Tsukune is in that state, considering how easily he managed to injure Gyokuro.
So, unless Gyokuro has a more powerful state to show us, I don't think we will see a more complete stage of Tsukune's transformation, after all, even with Tsukune's power increase, I still think, that Alucard is still too strong, for Tsukune to fight him, and apart from Gyokuro, there doesn't seem to be any other enemies for Tsukune to fight against.