The Barriss zeta is essentially a turtle strategy. You sacrifice virtually all offense to hide behind an unbreakable defense. You likely won't win many arena battles with that team but you also likely won't lose many on defense either. It's a solid team for holding your spot but not so good for climbing the ranks. It might come in handy on GW, tho, if that's something you're struggling with.
Right now, there's a big question of whether that unbreakable defense is too OP so one of two things is going to happen:
The community figures out its weakness and the meta shifts to beat it; or
CG steps in and nerfs Barriss or releases a hard counter.
Whichever outcome ends up happening, chances are it'll happen before you've farmed her and have her arena-ready. It might take longer, especially if the counter is behind a paywall, but as long as you're OK with the possibility that she'll no longer be arena-viable by the time you finish farming her, go for it. This logic applies to pretty much any strategy.