This is good stuff. You're open to suggestions and that's all that matters. Keep it up.
As a Gangsta Watch main, who has spent quite a bit of time in the respective character forums:
G&W>Ness. This matchup almost seems unfair. When Ness is recovering, G&W can FILL his bucket with one PK thunder and declare any hope for Ness's survival null and void. As an alternative, G&W can simply upB near Ness and blow him (haha) upward, far and away from the thunderbolt (not to mention the obvious fairs and bairs). Vice-versa, Ness's PK thunder just isn't as effective on a recovering G&W (awesome recovery) than it is on other characters. For off the map edgeguarding, Ness's best option would most likely be his bair, but it still doesn't compare to G&W's capabilities. On the stage, G&W can absorb all of Ness's specials (excluding PSI magnet for obvious reasons), matches Ness in speed and beats him in most ranged attacks. The only things I see going for Ness in this matchup are his deceptively heavy weight (compared to the lightweight that is G&W) and Ness's devastating backthrow for kills at relatively low percentages. That aside, G&W has the advantage. This is pretty much the dominant consensus by both G&W mainers and the Ness camp (notables like Ademisk included).
I also believe that G&W has the edge over Lucas, Falco, Pit and Zelda (characters heavily dependent on their projectile game), but I won't go into detail here, mostly because I'm lazy, and of course these are very much arguable.
Personally, and for several Gangsta Watch mainers as well, I have a hell of a hard time against Toon Link. Unstoppable projectile attacks, speed, combo ability and priority all go in his favor (in relative terms). I wouldn't go so far as to declare TL a counter, but from what I can see its definitely a trend.