Skyray STL V2 mod

I’m currently using this set up: 2x18650 driver: http://www.mtnelectronics.com/index.php?route=product/product&path=67&product_id=214 with an XM-L on a Maxtoch 31.5mm copper. I tried unsucessfully to get an amp reading so Im not much help there. Im fairley certain it would need some additional heatsinking if i were to get real serious. Maybe my expectations were too high and its doing all it can do. Should I look in to another driver,or focus on other areas? I’m not real picky as far as modes go. It would be great to have the option to go single mode, as well as L-M-H. Any suggestions?

Thanks,
Steve