How to DPS as a pre-26 Lancer:
* Heavy Thrust
* Leg Sweep
* Impulse Drive Impulse Drive Impulse Drive Impulse Drive Impulse Drive Impulse Drive Impulse Drive Impulse Drive Impulse Drive Impulse Drive Impulse Drive Impulse Drive
* Repeat

How to DPS as a 26+ Lancer:
* Heavy Thrust
* Leg Sweep
* Full Thrust Combo + Life Surge

The class really opens up at about lvl 40 (like most classes) when you have options, gap-closers, debuffs, etc etc.