I'd say just farm good mods for Phoenix for now then gear something else. They become seriously fantastic in a lot of the late-game content (among the best teams in HAAT and Sith Raid), but for that to work you need to have at least a couple Zetas for them and if possible you'd want to swap Chopper out for Sabine (if you can get her Zeta'd, especially).
However, Zetas are probably fair bit away from you right now, and even when you get them there are higher priority Zetas than the Phoenix ones. You'll probably find yourself coming back to Phoenix at some point in the future, but for now G8/9 should be fine.
