There is this older mission 1AU where the sun burns you and you have to hide in the shade, that would be good for implementing in a strike. A meteor shower would be challenging also. Options for using the environment against enemies like rocks which you can shoot down in caves that are on the ceiling. Stuff like that I would love.
-
I hope you're joking lol. The sun thing? That's in a strike already, when you fight the wardens servitor from the prison of elders.