Heeelp!!!

I would suggest outside of what you're doing to star and gear up General Greivous. If you don't do this... dare I say... it would be a very grievous mistake. ;)

I had G12 Ventress, G11 Grevious, G12 Dooku, G8 B2 and G8 Magnaguard and I barely managed to get Padme 5*. I think Grevious, Magnaguard, Ventress, Nute and Droideka are pretty big on this...new characters/new kits are likely to be more helpful...

Your question is impossible to answer.

Dooku's leadership underwent a drastic change, but was released shortly after the first event, so no one actually tested it for the event.

Also you can not know if it is appropriate or not you go after the Padme since we do not know how is your acquisition of legendary characters.

I tried with Poogle g6 + 3 geo g11 + Assaj g12 + 1 MK6 mods and I could not close grade 5. Eventually I'll work on Geonosian mods and use my Dooku g10 to try to release it, since with rework it can be viable. I just as you are risking since I do not care so much for PVP and I will not do crystal craze to release it.

Plenty of ppl unlocked with basically just g12 ventress