Here is my shameless plug! I made an AoE Grinding Video recently, finally got it posted. It is an overview of the basics of AoE Grinding at level 29+ as a Grenadier.
-Grind in PQ area after prime time; lots of mobs to be had and the extra influence is a plus!
-Keep "Flak Jacket" up and use "Ancestral Inheritance" for the extra mitigation.
-Use a solid set of wounds/toughness gear. You should have around 5500+ health by rank 29 if you stack wounds! In the video I only have 4500, but that's because I have been playing Rifleman and don't need to stack wounds.
Anyhow, check it out, might be useful for you!