Paper Mario definitely should have been an available character in at least one of the Smash Bros. I mean, how many same character variations do we have already? There's Pikachu and Pichu, there's Mario and Dr. Mario, there's Link, Young Link, and Toon Link, etc. Paper Mario could have been his own unique character. Here's what his move-set could have been.
B: Hammer
B← →: Spinning hammer swing (spins forward swinging hammer)
B↑: Paper airplane transformation (briefly glides forward)
B↓: Ground pound
A: Punch, kick
A← →: Bouncing paper fireballs
A↑: Partner attack (attack varies depending on which partner you have out)
A↓: Switch partner (quickly swaps out your partner)
Grab/Throw→: Pulls back hammer and then swings it forward
Grab/Throw←: Quickly rolls up into tube form with opponent, then uncurls to toss opponent backwards.
Grab/Throw↑: Holds opponent over his head then does a jump punch to send them upward.
Grab/Throw↓: Pushes opponent down then down spin jump on top of them.
Jump: Jump punch (1st jump), Spinning jump (2nd aerial jump)
Taunt: Raises hands and turns left and right, like when you win in the Glitz Pitt.
Smash Attack: Summons the Star Spirits who rotate above him and stop on Skolar, who unleashes Star Storm on those in front of Paper Mario.
Strengths: Strong, fast
Weakness: Light (goes flying easily)
Partner’s follow right behind Paper Mario, similar to Rosalina’s Luma. Depending which partner you have out, the attack they use when you press A↑ is as follows:
Goombella – Mario throws her, and she bounces off the opponent
Kooper – Mario kicks Koopers shell outward to hit opponent
Bombette – Mario tosses her out and she explodes (Like Link’s bombs)
Flurrie – Mario squeezes her and she blows a wind that keeps opponents at bay
Yoshi Kid – He throws an egg at an upward angle (like Yoshi’s egg attack)
Bow – She turns Mario transparent and immobile for a few seconds, where he can’t be harmed (similar to Kirby’s rock form)
Vivian – She unleashes a stream of fire (like Bowser’s fire breath)
Watt – She sends out a static shock (like Pikachu)
Sushie – Mario squeezes her and she spits a stream of water (like Mario when using F.L.U.D.D.)
Lakilester – He throws out a spiky ball
Tippi – She flies forward and comes apart, then comes back together around the opponent and pulls her into Mario for a Grab
Alternate costumes: Different colored suits