I tried out SSB on ny friend's Switch and so far have only played as Fox and Wolf (of course. They're the two Nintendo characters I actually like). Took me some time to get used to since unlike in PS All Stars, you need to knock your opponent out from the stage and your ultimate attacks don't guarantee an instant kill. I don't know if the overall characters just feel the "same" but I agree that each character in PS All Stars has their own characteristics. Pretty sure I've seen Nate missing his shots on Ratchet while Ratchet didn't even crouch - his short height proved to be an advantage!
That's what makes Smash so much better for me. The goal to knock people out of the level based on their damage percentage is much more fun to me than collecting those "supers". It's like playing Smash with 99% damage and then have the Smash Ball spawn every few minutes (which, yes, is something you can do.) If they were going to copy the formula anyway, I would have loved for them to copy all of it.
I main Fox and Wolf, too! With Falco and ZZ Samus following closely.