I have Han and Luke with maxed gear, only missing Luke's lead zeta. With good RNG I can get through over 50% of the phase before Grievous even gets his first turn. I use Han's stun on the B2, and ignore the other 2 droids usually, and just let my counter attacks kill them. I frequently have to restart at the beginning of the phase because Grievous will resist and then get a turn in so I just reset it. Getting Luke's special to get the debuffs and remove all turn meter at the start helps. I only ever target the other droids when Grievous' turn meter is really low or to get rid of that pesky B2. Also never use Han's stun on Grievous and save it for the side droids, especially the B2. I also use Han's Never Tell Me the Odds buff a lot, and helps him get his cooldowns to end quicker, and drop any debuffs due to the turn meter gain.
I tried it with Datcha lead a while ago and didn't do nearly as well so not doing that again.
I have 258 speed on Luke, and about 212 on Han, but this strategy has been working when my mods were a fair bit less too. If your Han is dying a lot then I would focus on giving him more gear. Mine stopped dying when I started adding gear 12 pieces if I remember correctly.