*hasn't read whole thread*
My 2 cents;
You want to be far away from GaW. if on large stage you will win by keeping your distance. Do not try to get to close and pressure him, and try to kill with moves like Uair in preference to smashes (if smashes miss GaW will be close to you. If GaW is close to you he will do damage). Zair is good if he starts to pressure you. Be wary of a spaced Key, it can get past an Uair and it can KO you if its not diminished and you are on high %.
Moves that are good : Uair, Bombs, Boomerang, Zair, UpB(in some situations only though, i think it can kill which is why i mention it).
Moves that are bad : Fsmash, Dair(it can be Uaired and then you will be in a bad position), Arrows (i think they are too slow a lot of the time, and Bomb and Boomerang are better options), Grab (not worth the punishment if it misses, and its easy for a fast character to escape, only use if they are in a form of lag)
Bad things to do : Trying to hit GaW whilst he is recovering from below the stage, Get too close, Trying to land near him when getting to the stage
Good things to do : Spamming bombs, spacing with Zair, Guarding the edge with projectiles - be ready to Uair if his UpB goes above the ledge, DIing away from him when coming in for landing.
Good Stages : Final Destination, Pirate Ship, Pictochat (IMO).
Bad Stages : Battlefield, RC, Norfair.
Id imagine the larger stage-part (ship deck) of Halberd would benefit Toon Link, but the first part is really good for GaW.