As for the MU in SSB4... I don't really know. The Falco vs Ike discussion on the Falco board had like 4 posts. I don't think anybody really has a clue on that one. One post suggested evenish, but that was about it....
Laser changes are a pretty big deal for Falco for sure though. I'm not sure even keeping his old Dair would have saved him from his awkward current location.
I keep mentioning in the OP of the MU discussion you can ask for fights and that playing with each other would be great for the MU and for fun, but nobody bothers.
Ratios, I don't care for, but even then, Falco usually gets slightly disadvantaged and even at best. Little Mac's discussion seems to suffer from For Glory Little Mac clouds and it's the only one where Falco players feel is 60:40 and two people even said if you throw Little Mac off the stage, he's done because Falco's a good edgeguarder. This assumes Falco's slow grab can catch Little Mac and this assumes a Little Mac who's an idiot.
His old Dair wasn't a throw this move out and hit everyone because it's that stupid. I'm looking at you Luigi Nair interrupters. Anyway, his Dair needed to be set up which in Melee and PM, you could do with Reflector and I don't really know what you could do in Brawl other than abuse Blaster's auto-cancel and stall the opponent to set up a Dair. The fact it was a fast was what made it good, but it was also a strong spike too. That was a bit unnecessary. A frame 5 spike that powerful? Two options if you want to keep it as a spike: slow and powerful like pretty much everyone's spike or weak and fast which I can't think of anyone off the top of my head. Other options would be to completely change his Dair which people might complain... and they will. Even if it was kept as is, people would complain because complaining is just something people do.
It's having double the startup on Dash Attack, the end lag on Blaster, grab made slower by 2 frames, slower than Ganondorf's, and Bair being Wolf's in animation wrecked Falco's kit. There was no real reason for Dash Attack to be that slow, Blaster wasn't balanced/fixed when stuff like Sheik's Needles exist, Luigi's Fireballs can fire the quickly while dealing more damage (up close), and customs projectiles such as Fox's Impact Blaster, Rosalina's Shooting Star Bit, Link's Quickfire Bow, and Toon Link's Piercing Arrows are considered Falco lasers, but better, grab is ridiculously slow for its range, and Bair isn't that good when you factor in Falco's air speed and losing a front hitbox to make his disadvantage less painful. These minor changes would take a small overhaul to fix Falco since Bair would have to be reanimated and the other moves would probably would have to be reanimated to fit the changes in hit frames. The time the developers can make other fans happy by making DLC characters, stages, and modes completely outweighs anything that can be done to fix Falco. Even landing lag changes could be considered too much, "wasted" work. Adding knockback and damage might actually break Falco more than fix him.
I would not be surprised one bit that if Wolf returns, he'll keep his old Bair and Falco's is kept as is. Or Wolf gets Falco's old Bair to mix things up which would be a literal kick in the face since Wolf would, if he's Brawl Wolf ported over and tweaked, have two moves to help his disadvantage: Nair and Bair and even Fair and Blaster.
Also, apparently, I'm the genie who shows up at the mere mention of Falco's name on Smashboards and not Shaya.