The main difference between the two is
timing. Disregarding Melee's edgestall infinites, a successful edgehog is a matter of grabbing an edge a scant few frames before an opponent, or getup rolling with near frame-perfect timing. Edgetrumping is the art of grabbing just
after the opponent does, and then jumping back and killing them before their lag ends. If things don't work out, then edgetrump lag needs buffing is all.
Rage? Rage is a promising mechanic (rewarding stock longevity with extra kill power) with a lot of flaws.
What do I think should be done?
- Add a Rage multiplier to hitboxes - this will prevent Rage from punishing combo setups and flurries, while still enhancing killing blows.
- Make Rage relative to weight? - On the one hand, this will prevent lightweights from suffering due to being bad at utilising the Rage mechanic (E.G.: Jigglypuff gets max Rage at roughly 90%, while Bowser gets at 150%, and both get the same boost) but on the other hand, Rage benefits heavies, who are lacking in general, so...
- Nerf Rage... somewhat. 10% maximum boost? Make sure it doesn't stack with the KB boost from damage?
Of course, there are probably more elegant ways to implement Rage to start with. But it IS better than L-cancelling. Really only Sheik's needles can force a whiffed L-cancel. Other than that, it's nothing but luck from the opponent's perspective. It's impossible to reasonably predict when someone will botch an L-cancel, and only in some circumstances can it be capitalised upon. And unlike teching, there's no reason to fail on purpose, because you can just succeed and then... wait.