I have to agree. You're off to a great start. It was not only playable and easy to control, it was fairly solid and enjoyable. You had some good creative ideas going there. Especially with Trevor, who has strikers for special abilities.
The only thing I would say I found rather annoying was the abusable of some specials. Some moves can be used to bypass the entire stage almost, since they make you invincible and go through enemies. Simon is very abusable. Alucard runs a little too fast too I think.
As for your request on a resized Saturn Richter; I have already done such a thing. I didn't do every frame, but I believe it should be all the frames you need. I didn't touch up any frames really, so its a bit crude, but I used a scaling method that is 100% exact to SotN scale guaranteed. I'm a real hard ass when it comes to quality, so I wouldn't make something available that wasn't done right.