they will keep on with LoS for a little while, maybe 2-3 more games, then either in between or after, go back to the original timeline, OR try another approach. EG let other devs take a crack at it. So we would get different vanias by different devs with different flavors and ideas.
At least thats what i could imagine them doing, but realistically, I dont think I can see them doing that... Like Cappy and megaman. they probably wouldnt do that.
they SHOULD, buuuut prolly wont.
I still think they will keep the original timeline around and occasionally release a 2D game for it, though i doubt we will see another HD. Who knows, maybe on occasion we might even get a 3D attempt.
I dont think Konamis done with the original timeline. Not by a long shot. theres still a few things that can still be done. especially in terms of merchandising and other media. (Anime/mangas, etc) The timeline may be bloated and full, but theres still room to expand into other mediums.
A Multiversal approach is neat, and its something megaman has done before. (The battle network and Star force games inhabit the same timeline in an alternate universe, so where Classic -> X series, in the AU its BN -> Star Force) so here we woould have where Lament of Inn. -> Castlevania 3, we have LoS -> whatever LoS2 is named
i think as of other M, metroid jhas it too, since other M doesnt acknowledge the prime games, making them a what if Au thing