With my electric MES, after and before every cook, I raise the smoker temp to max. and hold it there for a couple hours to kill all the bacteria and cook any fat that has been left in it.. Sure has reduced the mold etc...
The steam clean thing sounds like a good step for prevention of grease build up... and killing any bacteria etc...
Have the drain valves open and flush them.... Keep the heat on to dry out the smoker...
I leave intakes and exhausts wide open for air flow... I think I would crack the CC door and FB door also... In my electric, doing so has put an end to mold growth... I think it's the air movement.. etc....
If you can get it clean after every smoke, you are doing yourself a really big favor..... Let the fire burn out and burn up all what's' left.... then scoop out the ash into a metal bucket.... Even think about rinsing out the FB, if it's going to be awhile before the next use.... Wood ash mixed with water or humidity, is a big problem... corrosive as can be....
I've heard of folks that spray their smoker with cooking oil, when hot/warm, can't remember which, for a rust prevention step... I might use high temp paint for that step... flat black probably... OUTSIDE ONLY.... Cooking oil on the inside... ESPECIALLY food grates....
If this post is disjointed, it's early morning... 3:30...