In 10mm I use Alpha Strike, though I haven't used the rules for artillery and aerospace yet.
For 28mm sci-fantasy-ridulousness (aka 40k Apocalypse that is actually fun) I use the first edition of Warpath (basically KoW in space). No artillery or aerospace, but it does have flyers tanks, infantry, etc, in a ruleset that is super fast-playing, easy to mod (we've made rules for Titans) and fun.