20% online (mostly dogfightsservers with almost full switch like Warclouds, playing with two or three mates).
Rest is offline. I have begun one campaing and I see there is A LOT of more campaings to finish..Homever I am a moviemaker too, so most of the time goes in FMB to make mission for videos etc. It´s a long time I did a IL-2 movie, have been doing Lock On movies lately. I have a mission/idea for my next movie though, but it takes time!
Playing offline is fun, but the AI is stupid...or sometimes über..
What I like offline is the freedom to make own missions, fly whatever I want etc. Online is also a lot of fun, more fun if you have some mates on teamspeak covering your ass! If I play alone, I always end up in a furball being shot to pieces by hardcore player. Feel it´s more fun offline as I can choose the skill of the AI. I am not that bad, it´s just that when online, it´s the same persons shooting you down...and they maybe play just online to be good. Sometime I make my own server with only myself and some mates and we often have 2 on 2 battles. That´s a lot more fun than a big server because who know who you shot down!

Nothing can beat sneaking up on your friend, shooting off his wing and see him barely bail out and then make a perfect landing collecting 200 points!