Your friendly neighborhood PhoenixAZ here, looking to offer more help if anybody needs it.
A) A tip most higher-level players are using now: carry a repair droid to bait out GR units. Since most of our load-outs now are jets/jumps, do the following:
1) Trip dekO (and SC, if desired).
2) Let entire first wave of GR spawn.
3) Lure dekO and GR troops out with a repair droid.
4) Either line up Kessnipe on SC/barracks with dekO or ambush dekO and SC troops with jets/jumps. The first GR wave will be stuck on the repair droid and will ignore your forces. Remember not to deploy any mech, or your repair droid will move, get killed, and the GR/SC troops will switch their attention to your forces.
5) Drop any mech you may be bringing, probably TX-225s.
Of course, wherever possible, you'll want to lay out your troops where they will then proceed to take out the barracks, or as many of them as possible. If you luck out on a fairly weak base, you can split your forces, with some ambushing the GR troops and the other half going to town on the base.
The only real "trick" here is using the repair droid for bait.
B) If droidekas are not present, you can use spawned GR units for a Kessnipe. Lure them out with a repair droid, line up Kessen,and fire. Works best with clumped stormies, so Kessen doesn't kill the sniper/Rodian/dewbacks before he fires the supershot.
C) Of course, as some have pointed out, another viable option is to lure the GR troops to one side of the base while you launch an attack on the other side and just plan on getting to 50-60% before the initial wave makes it back to wipe out your forces.
Hope this is helpful to some. Feel free to correct, add to, or criticize. Cheers!
Chasin' after my fortune & glory~149,500 medals. Newborn Prestige Base. Free to play (use air and SC only in emergencies). Rank 30. Not bragging: these stats tell you what I am seeing at my level. Your mileage will vary.