Same as jackaboo, I use...

6-6-6-1
0-6-0-6
3-0-6

I typically do this when I solo:

1. Cast Empathy right before I reach the group of mobs
2. Run into the middle of the mob with guns blazing, take out as many as I can until I am at half health
3. Cast Transference, which damages mobs and heals me to full
4. Cast Suppression, which freezes most or all mobs
5. Cast Pain, hopefully I am currently targeting a mob with decent health left
6. Cast Empathy
7. Switch targets and take out a mob with guns while waiting for Pain to detonate
8. Cast Transference
9. Either clean up the few mobs that are left, or repeat, starting from Step 4

The second level in the UC Shipyard (Biosphere Deck) is an excellent level to solo using this strategy. I leveled from 32-38 very quickly doing this, and even the mini-boss at the end of that level is very solo-able. It was so satisfying that I started letting out a maniacal laugh using the LOL emote after slaughtering each group of mobs.