Empire Team improvement advice please :)

Preataunters die rather early from Phase 3 onward, I would not recommend Shore if you aim for more Combat waves, as even at G12 you'll likely lose him in wave 2.
Are you running a separate Trooper team? If not, you might want to switch in DT, his deathmark can be of some use. You can try replacing Tarkin as his damage is not outstanding and his debuffs rarely stick after Phase 2.