I've been playing around with a new indie game that has just been picked up by Steam. It is very much a spiritual successor to Ace Combat (evening including superweapons and super planes), one of my all-time favorite series. It is currently in alpha state and has some rough edges but is very stable and has lots of great features. Updates are released regularly with new aircraft being added all the time.
One really nice things is it is being built with modding in mind. It comes with a mission and skirmish generator, and adding new aircraft and schemes, music, editing stats, and just about everything else is very easy. I've already done a paint pack for it.
You can find more about it here: http://store.steampowered.com/app/242130/
I totally recommend it if you like those kinds of games.