I don't remember having trouble with MoF.
I didnt hate it's weird story either. In general I felt it was pretty easy to accept the LoS games as their own thing with their own take. I didnt even mind Trevorcard.
Also you say "no reason" but all things said, Gabriel never actually learned Trevor's name before he died. So, since he's Dracula, he named his son the opposite, because he stood against him.
As for looks, well, LoS made a point to say how vampires start out beastly and ugly and only the really powerful can take on human form.
Alucard was turned by Dracula himself and is already powerful, so hey, shortcut, but he's also blood starved. so visually, he's a few steps below Dracula.
I kind of liked his design really. What made no sense is how the moment he becomes alucard suddenly his hair and facial structure change entirely and thats just dumb