My schedule is like this:

Honor: S2 mace, S2 helm, <I'm here> S2 shoulders, guardian/vindicator stuff
Arena points: <I'm here> S4 gloves, S4 legs, S3 chest, S3/S4 shield


So that I get 2 parts from S2, and 2 parts from S4.. to get the 4 piece bonus. Looks good? Basically I'm skipping the pvp shield because I think the 4-piece bonus will be more rewarding.