there are better kits to invest on than Phasma's leadership.. however, with UK here, it's more likely players will use him than phasma as leader for FO and FO hybrid builds.
that said, i'm still using phaZma as a leader, with Zylo, zthrawn, DN and Zboba, lol.
i invested early in FO, started Jan2017 , f2p. iLL probably switch teams someday soon, u have to keep up with the meta to maximize payouts. even if u dislike Rebels and LS, u kinda have to let logic take over rather than emotions if you want better payouts.
i compensate with mods. speed mods and potency mods. the rest are Rng when it comes to using phaZma leadership. its kinda lame i know, but, there are some form of synergy with random assists. It just wouldnt be consistent all the time.
You mentioned using a zavage? im not too sure about that though. i always pegged zavage to be used in Sith synergy or at least accompanied with sith assassin. they have 1-2punch combos i think.
Im actually interested in what youre trying to theorycraft with that particular build. more explanation from yourself is required before any other (more experienced) players can share their 2cents on it.
goodluck!!