First off let me say nice job trying to stick with Falcon in Brawl. You are already cooler than 90+% of his Melee users in my book.
![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
lol
There's been a lot of debate and trial and error done by the regulars here regarding aggressive vs. defensive playstyling. There isn't really a definitive answer on that yet, but I'll tell you what I see. In Brawl, Falcon is about balance. There are times when you need to be pedal to the metal aggressive with him, and there are other times when you need to be elusive and shield happy with him. The trick to playing him well of course is to find the proper balance in each character matchup (and with 35 matchups that's a lot to learn). From my experience, generally the best place to be during a match is close enough that your opponent won't projectile you, but far enough that he can't reach you. Certain characters make this VERY difficult of course (Link and Toon Link come to mind) but as you get a better idea of how to play against each character it gets a little easier and more natural. Until you find the correct spacing for each character matchup, you'll struggle to succeed with Falcon. Luckily though it doesn't take too long to figure out everyone.
Once you've found your correct spacing, you really have to start identifying your opponent's moveset and think about what they're likely to do/what you're likely to do and what will be the probable defense taken by each. Falcon Kick is wonderful for this reason because it's fast enough that you can get it in when you're in the proper spacing area without getting shielded everytime. Pretty much every other move in Falcon's arsenal is slow enough to be prepared for by your opponent if they are not busy doing their own move or focused on recovering and stuff. Falcon's running speed is great too because you can work in Running As a lot on people. He's quick enough that you can approach from your proper spacing and get them with it. These two moves are at the core of Falcon's playstyle in my opinion. I've yet to see a good Falcon who didn't utilize these moves often.
In closer combat, look to the simple yet often overlooked AAA combo. Lots of people talk about the fists of fury being punishable (the held rapid punches after the initial 2 jabs + Gentleman Knee), but honestly I've found that if you hold A just long enough to start the fists of fury and then immediately let go, you are able to get valuable damage in with the fists of fury and then stop before your opponent can punish you. Falcon's tilts/Falcon Kick/Raptor Boost also follow up well after this move. Honestly I'm a huge fan of the AAA combo so once again I'd say start using that a lot more if you don't already and it will improve your game.
Utilt is also a noteworthy ground move. Try spamming it. Seriously. The walk behavior of it is a totally unorthodox but sometimes very effective approach method. It has great priority and an enormous hitbox with good range so even if you get attacked you should be fine. Chances are you'll get your opponent before they get you though. I find this move great at places like Battlefield and Lylat Cruise where people can land on platforms at about your head height. Utilt works much better than Usmash at quickly reaching people above you on these low platforms. Also it is a great edgeguarding tool. If you're opponent is off the stage but close enough so that you can't really get a proper edgeguard aerial on them before they return, just spam Utilt. You'll probably hit them before they reach the edge since it covers the entire area around the edge. If they do get to the edge before you get all the way over there, stop a little ways back and do it. It punishes just about every edge crawl/jump, and if you clink them you can knock them back off the stage with the little slide that they do. Then you can try again. lol I'm a big fan of Utilt as you can see. Try using it more if you don't.
Falcon Dive (UpB) is a great move now. You can shield cancel with it if you have control stick jump enabled, and it has deceptive reach both horizontally and vertically. Very often when my opponent is in kill range and I can't seem to get a good hit on them, I will simply approach, shield, and then shield cancel with UpB to KO them or at least knock them off the stage. This is a powerful move that when used creatively can be devastating. Spamming it of course does not work, but if you're careful with it and use it when you're at least pretty sure you'll get a hit with it, it's well worth it and a much better option than a lot of other moves.
You pretty much know about the aerials from what I read in your earlier post. I won't get into those, but I will say that Falcon feeds on things like Running A -> Utilt -> Uair -> UpB/Uair/Bair. Stuff like that works very often and is so enjoyable to do. I'm going to make a "combo" list in the next couple days, so if you're not sure about followups and stuff definitely give that a look-over.
In the end, Falcon really comes down to personal enjoyment. You won't win against certain characters when they are used by competent players. The sooner you accept that and enjoy using him against everyone else, the better you'll like him and the better you'll become. You won't win any tourneys with him. The best you can do with him if you really want to win a tourney with him is to use him against everyone except his worst matchups, and then when those horrible matchups come bust out your secondary. It sucks that he's come to that but that's what it's looking like it's going to be in Brawl for him. I still find him a ton of fun to play as though, as do the regulars around here. Getting Knee kills are even sweeter now than they were before, because they show that you officially mindgamed someone hard. lol Plus everyone at tourneys pulls for you and hopes you "Falcon Pwn" some people with him. I dunno, in the end it really comes down to you deciding what you want to accomplish in Brawl. If you want to have a blast with you friends and have moderate success at tourneys, then go for it. If you want to be the next Ken, try picking someone different.
I hope my post has helped you in some way.