The highest DPS on a Boss or an Elite is 3 tracers, unload, Rail, HSM. If unload procs during the intial 3 tracers USE IT. Do not pass go do not collect 200 dollars, that is free damage and heat. Now on regular mobs use a fusion missile then go ahead and use thermal overrides on sweeping blasters (or death from above if it's up). Strong targets just use the above rotation, they should go down after HSM and Rail