You wake up on September 13th, 2014. You log onto Facebook/Tumblr/Reddit/Youtube/4chan/Smashboards/OtherMediaSite and find this to be the true roster.
After a bit of testing, the following is revealed: Jigglypuff and Ness play like their Melee selves, Ice Climbers can wobble, Falco is made less of a clone in his aerials and his Final Smash is the Arwing which plays like ZSS's new Gunship blast but his specials are their brawl selves. Falcondorf still exists but some of his special alternatives become magic or sword based. Lucas and Wario now have one special changed to their P:M identities (PK Charge and the Shoulder Charge) but are otherwise unchanged. Metaknight has been tweeked to have less stun and knockback in most of his specials. Wolf and ROB are identical to their brawl identities (edit: but are slightly "sped up" to fit the current game's engine).
I'd have Shulk, Ness, and Lucas. Most veterans would be back. If Wario loses his bike, I would drop him as a main forever and never look back. I could care less about King K. Rool, Marshal, and Waddle Dee, but I don't hate them.
In fact, I've come to dislike Waddle Dee a lot less as time has gone on. While the lack of Mewtwo is kind of annoying, I never really used him, so I'd get over it. In terms of balance, Ness being reverted back to Melee would make him worse than he was in Brawl. Jigglypuff would be good again so that's welcome, but Ice Climbers being able to wobble would make them stupidly good again. Wolf and R.O.B. didn't need to be changed so I'm fine with them being the same. Having not played any Zelda that has Ganondorf in it, I wouldn't really mind that he's still a semi-clone, especially because he'd still have the Flame Choke and Sparta Kick.
So overall, I'd be happy. I'd get the one newcomer I actually want (Shulk) I'd get all the Brawl vets I care about. There are some questionable balance changes (if Shoulder Charge does in fact replace the Bike, you'd have killed one of Wario's best moves) regarding Wario, Ice Climbers, and Ness, but overall seems pretty solid.
I would like to point out that Lucas's neutral special in Project M is not called PK Charge. It is called Offense Up, based on the support PSI of the same name.