Bets are placed XD
Oh! Not because he's more cartoonish (although that adds to it). In short, beside Frogger he's the oldest Konami IP (May 1986), been their mascot for a big chunk of their history, has more games than any of their IPs despite his last being in 2011 (Castlevania just cought up for that) (Technically his last was in 2017 on SFC mini, though that was just a port). Has one of the greatest music tracks in gaming (that's a game high point, not because I'm a fan).
Goemon games are a parody based on a real Japanese folk legend that goes by the name Ishikawa Goemon, a charitable theif/ninja (just like Robin Hood) lived in the 1500's (Edo era). He's also infamous for his end (I'll keep that for later if you're interested).
Goemon games are called The Mystical Ninja in the west, Ganbare Goemon in Japan (means, keep going Goemon or Never give up Goemon). A bizzare comical master platformer (if it didn't had the better camera I'd definitely say it surpasses Mario 64). Out of his 34+ games (not counting ports, that would be 54), unfortunately only 5 made it to the west (3 of were one of the greatest, establishing quite a fanbase), this was unfortunately due the Konami's conviction that many of the jokes wouldn't be understood by the west.
A platformer were you play using instant change between the 4 ninja crew. Goemon, the hot blooded ninja. Ebisumaru, Goemon's first friend the wacky fat ninja. Sasuke, the mechanical wooden doll ninja. Yae, the agent spy ninja. They're all based on folk names btw (except Yae, I'm not sure). I can of course delve into their excellent moves set that fit Smash perfectly, but I'll stop for the sake of not making this a text wall. (I'll say though, one of Goemon's moves is turning into a super sayian).
This is an epic music no denying, and although it's been used as an intro, outro and for FE stages. I honestly do think that epic music are a bit too intense for Smash. Or maybe because it's not my main cup of tea. I'd like to link some Mystical Ninja music, but thought it might ruin your epic mood.