I suggest you also look up this website for more in depth training. Don't worry you're not alone with Falco. In fact you should be happy you chose him because Falco and Fox are regarded as top characters in the game. I also suggest you never do Up B in battles as an attack, only as a recovery move as it leaves you vulnerable to attack when you free fall.
This is the website: smashboards.com
I'm al hell lot better with Marth than I was when I last posted here. And I also know of the Ken combo. It's a Marth specific move and it requires you to be sufficiently trained with the SHFFLs, and the Dair spike as well as the Double Fair in a short hop moves. Yikes that's alot to learn - I still can't do it effectively as I still have a bit of inconsistency with the Double Fairs. The Dair spike is currently being worked on.
The Ken combo is SHFFL Nair, SHFFL Double Fair, Dair. I'll post a youtube video of it here: http://youtube.com/watch?v=6_syhEbvmYU
You can beat bowser with this move in about 5 seconds - better than the Ganondorf move lol.
The ICs are fundamentally a combo powerhouse. I mean it. Once you get the hang of desynch basics with the ICs it will almost be like controlling two people at once. Their power in Melee battles come from desyncs and grab combos. Eg Grab, headbutt, blizzard, then a side c-stick throw instead of a side normal throw. Nana smashes the opponent while he's being thrown away from popo - instant kills for many characters with >120% hp if they don't know how to survive properly.
I also suggest you look up this video for advanced tech training - http://youtube.com/watch?v=4n4s5yB7ZkE