Was thinking about it for a second and I think I know what they could use as a gimmick for the Garuda weapons stat wise. Hopefully they don't take the same route as making melee/mage the only variety between them since they should prolly go about it like this. Garuda is about speed but speed doesn't just mean evasion it also means many other things like attacking, blocking and parrying so perhaps.

Marauder arm could have a +30 to parry
Gladiator could have a +30 to block rate
Lancer could have a +30 to Feint/Full Thrust activating even if you didn't miss an attack
Archer could have occasionaly fires 2 arrows or a very low delay.
PUG could have +30 evasion
CON could have a MATT 30 and 15 Wind potency
THM could have MATT 30 and occasionally decrease recast time of spells.

If they follow the concept of Garuda's speed then the top would prolly be a nice mix of traits to make them all useful in one way or another, it would enhance MRD/Glad/LNC/PUG ability to use their counter abilities, enhance CON's strength with wind magic and give THM the ability to recast their spells quicker.