Yup, it's just like that. The problems are a matter of interfacing (we need a refly button for DF-style, a start timer for coop-style gameplay and a list of existing aircraft that's possible to spawn into, that's all), but the underlying structure supports everything. It's just up to the mission designer and host to decide on how to use it.
For example, you could stick to "vanilla IL2" style coops by disallowing the players to spawn new aircraft via the relevant difficulty option, throw down some AI controlled aircraft over a waypoint with a loiter function and have your guys spawn into them upon mission start instead of creating new ones. As soon as they take control of their aircraft from the AI, each one exits the "loiter circle" and you head out for your objectives
