I always used the Ackbar, BB8, CLS, Thrawn, Ventress team when I was trying to do P2-4. It's pretty easy, and fairly forgiving on gear/speed requirements since you can stack ventress' damage in P3 where you can manage the B2's TM with CLS/Thrawn. It also has the benefit of easily swapping in Hoda/Yolo once you get them to 7* for a full solo. If you're trying a pure NS team, then it'll probably be a little more challenging (and maybe take a few restarts) since the whole deathstorm thing can be fairly RNG dependent, and they don't have any TMR under Talzin. I'd try to knock out 2 of your NS at the start of P2, then topple the tank with specials, spool up Ventress' offense with all the revives on basics, then once the tank gets up from topple kill the turrets with Ventress' special again. Make sure you are modding Ventress with a CD set, CD triangle, and Offense cross at a minimum. 6E mods will help, but aren't required.