Sparks?
There are a few that can do that already. There's two in specific that are useful in the Casual Emitters pack. Do you need me to make additional content, or will that be suitable?
Exhaust emitter
Currently, you can use things like the Cannon/Tank smoke for exhaust. Are these sufficient, or do you need something specifically different?
Wind has always been a thing but it's not in the environment GUI.
Okay, that's good to know. Is wind included in the environment files? I was thinking of making a few smokestack emitters, but I don't know if I should script in direction or just rely on wind. Judging by the majority of maps seeming to have no significant amount of wind, I will likely script in direction.
can you also make a quiet electric hum loop?
I'll need to check what I have made already, but yes, I should be able to do that if it isn't done already.