I like the idea that came out of this thread of implementing other, different, status effect immunity shadow sets.
A lot of people complain about 3rd class status effects (Stasis, CC, Masq, Howl, etc), and they're not wrong that some of these status effects are too powerful, and too easy to inflict. By making people have to make a choice on which status effect they want to be immune to, you inherently make the Unfrozen set less OP since there's now legitimate competition for best-in-slot.
I think the best option is to disable the Unfrozen Shadow set in woe/pvp until we get sets that actually compete with the Unfrozen set for best-in-slot. In the meantime, also making it obtainable via some permanent method (ie. put it in kafra shop and make it tradable, or the Shadow Analyzer from Camp's Modest Proposal), so that people who don't currently have the set, can obtain one and be ready to go once it's re-enabled.
I think these shadow sets DO have a place in WoE, but the system is just not fully fleshed out enough to be enabled right now.