This is a two part wish.
When you destroy town, the buildings are blown up but there is no smoke or fire. I think it would add a little "ambiance" to have some smoke and or fire in the town when it's destroyed. Perhaps have the radar tower in town burn just like the radar tower at a base would?
Also, when you drop ords, a hangar, dar, what ever, when it's been burning for awhile the smoke disappears but the fire stays. Wouldn't the fire disappear but the smoke would still stay as if what was burning was "smoldering" now? Perhaps make the smoke a greyish color after the fire has burnt out.
Just small ideas that came to mind and really don't think they'd be too much of an issue if they were to be implemented.