Hey Dog!
I find that the only thing that the wattage helps with is helping get the coil to TEMPERATURE. You want to keep Ni below 600F. When I'm playing with Ni coils, I usually set the wattage between 20-30W, and my temp around 400-450.
If I was going to play, I'd set temp around 400 and start watts around 20-25. Try a few hits. Bump the wattage - when the coil gets to temp, the mod is supposed to back off, so power isn't going to matter much. TC helps me with a CONSISTENT hit, but I have yet to find that I'm going to chuck klowdz on TC (I have other mods/builds/coils for that)