Let me actually do 5 *thinks for a moment*
1. Shulk: my obvious first choice. An original character with unique abilities from a budding new IP with a lot of amazing content that would fit Smash perfectly (and is first party). There's no reason not to include him, seriously.
2. Fiora: Xenoblade Chronicles is not likely to get a second rep, but if they did, Fiora would be my top choice.
3. Redone Ganondorf: Ganondorf does not deserve the clone treatment, period. He deserves and has potential for a completely original moveset without stretching canon.
4. Jigglypuff: honestly, my reason for wanting Jiggs back is mostly for nostalgic reasons. Someone I once knew would always pause during a specific frame of its taunt in Melee, and thus "Drunky-puff" was born. It would be a shame for that joke to not return xD
5. Krystal: I'm on the "Smash needs more female characters" boat, and Krystal would be a cool choice. I heavily supported her in the Brawl days, but now I'm more tepid. I'd like to see her, and I'd be really glad if she made the cut, but my hopes aren't high, and she's no where near as important to me as Shulk is.