don't bother trying to nair smash falco when hes at low-mid %, you are better off nair--jabx2--grab or nair--pivot grab. ALWAYS expect the sideb, especially from a falco because of his bad gimpable upb. i like to run back and forth shielding until he does and then charge a smash near where he lands. i also fsmash his illusion every time, if i don't have a yellow a CHARGED fsmash from any other seems to work, and you have enough time to charge it. you can also dsmash which is better chance to not get canceled out.
match 2 : "I like to spam grab on that platform so if they jump up i can throw them off stage" -- they can bair you and it cancels out your grab, as well as snakes bair and mk's shuttle loop, etc. so be REALLY cautious when at med-high % if you do that, it works 70% of the time, but you can still get hit before you grab sometimes
seems like you just need some tech skill work, like not wasting double jump when being cg'ed, no killing yourself even though the pikmin did it. stuff like that
im not sure if this is true, but can you qcdi or smash di out of falcos jab before he can grab you?
oh, also, if you see him spike you try to put it in your system to tech every time, no matter what, and even if he doesn't hit you you would put on your shield instead of teching. you get eaten alive by his chain spiking and then roll towards in mid of stage, where nearly every rolls and they always charge a smash there. so, if you get spiked on the stage when near the edge, try getting up with an attack, i noticed that falco uses dsmash so normal get up there won't work so well. be sneaksies