And I disagree on the Trevor=Alucard thing.
It's not impossible but highly unlikely.
Trevor was born BEFORE Vampire Gabriel.
Well, the info we have says and/or heavily hints that Trevor never returns from his confrontation with his "father," Dracula. I'm thinking that he may be somehow vampirized, but perhaps the mirror/God/Devil masks* have something to do with it, thus him being cursed, yet still retaining his human side.
But I'm still hoping that's not the case. I want them to be separate, but considering that LoS already fused Leon with Matthias, anything's possible now

*concerning the God/Devil masks, wtf happened with that plot device? Now there's this mystical mirror(s), but what about the masks?? I NEED TO KNOW