Pretty tough decision, but I think Luigi and Pacman are the best

Poor Luigi
Even in beta he's still overshadowed by everyone

I feel like the development team did a great job with translating the Sm4sh characters (Pit, Luigi, Falco, Pac-Man, G&W) so they feel very familiar. I voted Pit in particular.

For some reason, I don't find myself enjoying any of the *true* newcomers, like Luffy, Sandbag... and especially Bandana Dee. Isaac is ok though.

I don't enjoy Bandana Dee too much either.
Aside from the fact the canon moves could have ended up as perfectly viable in his moveset, the end result doesn't exactly fare too well.
God, I hate that Side B & Dash Attack, they're just so unsatisfying. Specially Dash Attack.

Isaac is really fun!
I gotta admit, his movesets are fun! Also a Golden Sun fan here.

As for Pit..
His aerials are so satisfying. I don't know why, but i really love doing Pit's aerials.

So it's Isaac and Pit.

Bowser and PAC-MAN for me.

I always loved heavyweight powerhouses in the Smash series, and with Donkey Kong being the only one in that category in SSF2, another one was definitely needed. I like the way Bowser was put in; he's super powerful and difficult to KO, decently fast, his Fire Breath in this game being MILES better than the one in the actual series, and has amazing grabs and aerials. He has a great combo starter with uthrow, dair, and late nair, bair is a nice edgeguard, and fair and uair kill stupid early. Flying Slam / Koopa Klaw is as fun as ever and so satisfying to land (though now harder to Bowsercide), and Whirling Fortress is as useful as ever. His air-to-ground transitioning, something that plagued him in the official games, feels a lot smoother in this game.

As for PAC-MAN, he has some very fun and useful techniques with his specials. Bonus Fruit is useful in any situation, and him being able to use it when another fruit is on-screen makes it so much better (spam Cherry near the edge - a simple and effective edgeguarding tool). He's also able to insta-grab Bonus Fruit to make it more useful, and Power Pellet and Fire Hydrant are as good as ever. Bonus Fruit and Fire Hydrant are also compatible with PAC-JUMP's trampoline, which can lead for some cool and interesting tech. He also has great attacks - jab, dash attack, ftilt, utilt, and fsmash are all useful, and his aerials, namely fair, bair, and uair, are all very fluid and give him a great air game. Nair and dair are also good for the right situation. Finally, PAC-MAN's grab has been improved imemnsely - it's still unsafe to use, but is a lot more versatile than in SSB4.

tl;dr Bowser and PAC-MAN in SSF2 are what they should have been in SSB4.

My boy Isaac taking that 22%. With his Cyan palette swap.

and

Dee with Isaac as a close second