Min gear required

You won't need to. And you'll have plenty of time to get the last two to 7* hopefully if you have crystals set aside.

I won't be spending crystals on buying packs. Jolee and Zaalbar are around 3 and 13/100.

I've got Bastila at 85, G12 zeta'd, Jolee 85, G12 zeta'd, Big Z 85 g8 no Omegas, Mission 85 g8 no omegas, and T3 85 g7 no omegas. I really don't care about Z, Mission, or T3 after the event. Will the penultimate at tier 4 trip me up?

@MasterGoz read the comment above yours. Clearly it won't.