R2D2 event ... how good does my Empire squad have to be?

It was four months between the first two Emperor's Demise events...don't know why people keep assuming six.

Anyway, your team comp is good, just gear and mod them better. I would not call gearing tfp, Vader, or RG wasting gear at all, as all are heroic tank toons. Post-rework, Tarkin is esteemable as well.