Multiple choices for Z - yes, another thread about this.

I think you want to play with Nihilus lead. And you should go for it. Then you will face a lot problems with debuff and speed until you get good offence mod set(with high speed secondary) and GKenobi.

However Nihil lead is very good counter to rex, gk, zbariss, zmaul, team is hard to be obtained.

For your option; I think kylo is the best choice at that moment. Then your guild is ready for HAAT, you can zeta your Sid