Increased hitstun is worth a try, but I don't think it's going to fix the balancing much. And if L canceling proves to be too hard to re implement, might I suggest simply make an auto cancel happen no matter what? (excluding Snake's aerials, and "stall then falls"... the second one's a maybe). This also has the benefit of being a "binary" condition, it either does or does not happen, and is more likely to be accepted because of this. And if you really want to make it harder to camp and spam projectiles, why not just increase the cool down on projectiles, preventing the spammer from simply Dsmashing (or whatever countermeasure they deem appropriate) as soon as you get close? I don't totally buy it that you have the source, but all I care about is whether you can change stuff or not.
If Brawl is hacked to the point where we can re balance it, maybe some kind of official SWF re-balancing could be devised, and pro-SMW rebalance could boycott any tournament that doesn't have it to increase distribution. If this ever happens, I'd like to suggest an increase to Sonic's air speed, allowing him to combo more and making him feel more like he did in his games. In the Genesis Sonic games, your acceleration was doubled in the air, not slowed to a crawl.
That gives me a nice idea for a "just for fun" thing, make characters play more like they did in their own games, wherever possible.
Also, it was really brilliant of Sakurai to put tripping into Brawl. Seriously, what Sonic fan doesn't like seeing the best runner period slipping and falling, then forgetting he can just roll into a ball and make it an attack... HOW DID ROB EVEN TRIP? he has treads...
So, yah, I like the code, haven't tried it yet, but I already have the homebrew channel on my Wii.