...I installed a speed controller on the fan of my smoker...
Would love to hear how your controller works!
My approach is to use the controller that came with the unit, but have switchable resistors (50,100,200ohms) in line with the fan power to cut the air flow way back after start-up and temperature equalization. This is not without safety issues however, which is why vendors design these as conservative as they are. They don't want fires going out, augers feeding lots of pellets, and then folks carelessly restarting a flaming ("scary") mess.
Granted I'm a water pan guy in all my cookers, but the basic design of pellet machines make them operate dry to begin with so bear with me as I promote them here. But to get consistent (and high) heat to the pan in a pellet machine, I add a 400W hot water heater element so I can actually
see steam. Even if you like to cook "dry", a little supplemental electric heat is useful in a pellet machine...that way you'll spend more time smoking pellets and less time incinerating them.
But not from the igniter rod in the pellet crucible! Pretty sure my "hot rod" only is powered for the first 15 minutes of startup...I know of no conditions that would re-power it. But if anyone's pellet machine does, I heartily endorse the cut-out switch idea, if only to preserve the lifetime of those igniter rods....which have a high power density so aren't prone to long life anyway.