Peach - Obviously the hardest match up, float cancel slaps grabs and downsmashes make this match rediculous.
Marth - Retreating Fairs, stationary fairs and dtilts are fast and safe, he edgeguards Ice Climbers SUPER easily has a huge grab range and has invincability when he throws, Marth runs at you grabs forward throws then ken combos nana off the stage, has a great recovery and then solo popo is annahilated. I only wish I were exagerating how easy this is for him.
Fox - a 3 frame move that will instanty kill nana if she is hit, fox is the hardest character to grab and he has an awesome forward throw against ice climbers as well, he can attack your shield with impunity, he out maneuvers you and outside of the damage he can do except for damaging grabs, he has every single advantage except recovery and once he has hit nana once and comboed her to her death he has a better recovery than you as well. Technical foxs **** ice climbers, I have played silent wolf and lesser technical foxs to vouch for this.
Falcon - Knees and forward b are insanely difficult to deal with, forward b often pushes me too far to punish, if it hits its a guaranteed knee, if nana is kneed she is probably dead, if she is stomped she is definitely dead, Falcon owns sopo. Also he is really **** hard to grab.
Ganon - Kills nana in 2 hits and outranges you, this is severely easier than fox for me however because he is at least easy to combo chain throw and edgeguard.
Jiggs - She is floaty but f-smash seem to wreck her pretty hard I think this match is fairly winnable, even in ICs favor.
Luigi - Floaty so hard to do good grab combos against, he is pretty slow in the air though so it makes it easier to predict his aerials and punish him with f-smash, also on the ground you can simply shield most of his approaches.
Binx a lot of the stuff you are saying seems to only possibly work within a window of a few frames. Even if it DOES work, it's probably too risky to attempt unless you have robot precision like m2k.
You say to make sure he dies when you grab him, but you have to realize this isn't always possible when the Falco is good at smash DIing out of the chaingrab. The options are basically attempt to chaingrab or do a smash. If he attempts to smash DI the chaingrab and you smash, he's probably screwed, and if he attempts to DI the smash and you try to chaingrab he just gets grabbed again, but if any of the opposite cases happen Falco is basically free. It becomes a guessing game and guessing games never always work in your favor.
Also, I know Falco dies really easily but it's getting the initial hits off that's the problem. He's like impossible to approach and it's really hard to work your shield game well on him.
Any tactic that can be mastered should be, it isn't any more risky than rolling, if falco predicts your role the best case scenario is that he wittles down your shield some more and shield stabs you with the drill anyways.
You can reverse dair falco if you expect him to smash DI away this will put him right in front of you for an easy regrab, also someone mentioned just fsmashing him, also uthrow to dash attack and tech chasing works very well on falco.
You can try learning to do a dashing powershield this is almost always a guaranteed grab at medium distance. You can jumping blizzard into a laser and nana will keep going trading damage with him, this also forces him to act and you can take advantage of it.
Basically I try and stick to the ground because all of his approaches either outprioritize your aerials through speed/position/lasering you out of them or dont do enough to him afterwards to make it worth the risk of being aerialed out of them. If you manage a grab he should die, and you should be able to manage a grab because he doesn't run as fast as you, waveshields and upsmashes are your friend, just keep coming at him sooner or later he will be cornered and once he acts you react and he loses, just keep your cool, play against him like you would Marth vs Mario, pressure him towards an edge with presense and being careful, once he jumps or rolls you get a free aerial or grab, if he jumps strait up to shoot a laser then wavedash forward and fsmash he will be off the edge for the price of 3% damage.