Next farm: Revan or C-3PO?

It's hard to know what future will bring for the game, i.e. what would be useful in a new raid. Naturally I farmed for both in my higher gp. In your case you are just 1 toon next to a meta rebel team, so answer should be obvious. Solely getting Revan won't get you the team, there's much more investment on getting that team ready. For last consideration what does the farm itself get you: ewoks are a fantastic team and the event is very hard. You gotta gear them properly which returns you a ga/tw team. Revan farm will yield you 2 toons that will get used in that team and the event is a cakewalk. The other 3 you may never use unless you later decide to the Qi'ra team.