I really like Skull Kid's desing but I would prefer Impa as the zelda newcomer, because she's one of the important recurring characters in the zelda franchise. Anyway, I get that Skull Kid and MM are popular among Zelda fans, so I hope Impa gets in as an echo
Well I don't want to bring up the whole "Gardevoir Gothitelle make sense cause it = repping all the pokemon gens" argument cause i know how that goes around here (all the gens at the time of the roster being decided and saving gen 7 and possibly 8 for DLC) BUT on the subject of Zelda and trying to represent multiple games in a series for Ultimate something similar could be happening:
We have the whole zelda franchise having characters reworked to represent different zelda games:
Zelda- link between worlds/link to the past
Link/Sheik- botw
Ganon/ young link- Ocarina of time
Toon Link - wind waker/spirit tracks/phantom hour glass/ 4 swords or minish cap...all the toon link looking games haha
So getting Skull Kid as a Majoras Mask rep would be cool cause it further represents another zelda game (oddly enough twilight princess has been dropped even though it was the standard design before).
now that said with skull kid you could take it further and say impa will also get in as an echo fighter and could have her skyward sword design representing yet another entry in the zelda series (hyrule warriors design could also be used for impa but i think main line zelda games are more likely for design choices in smash).
theres also something interesting to think about if that is the case: we got Ridley at E3 and then Dark Samus as an echo in the smash direct... we then got K rool in that same smash direct... we could potentially get Dixie kong as an echo shown off next time we get smash news. during the next time we get smash news its also possible we get skull kid revealed as a newcomer. we could then get shown an impa echo in some future smash direct or something before the game comes out. if that happened there'd be this pattern of getting newcomers and then in the next information drop we get an echo fighter from that characters series shown. just a cool possible "pattern" that seems fairly likely given how likely dixie/impa/skull kid seem to be at this point AND the fact i expect some nintendo online direct to have smash info in september (we know nothing of ultimates online capabilities) and then at least one more smash direct (if not two) at some point from october-december7th probably focusing on the story mode. so at least two more smash info drops is fairly likely, id be surprised if we only got one in the next 4months, seems the game was held off from showing anything until E3 so they can hit us hard with info and hype in the lead up to release.