I feel like if you've already played Insurgency then you should already have a good idea for yourself. They are completely different games. I feel like they shouldn't even really be compared.
I have played Insurgency and EFT as well. EFT has persistent elements, while Insurgency is more about playing "matches" in a more traditional multiplayer sort of way. I love them both and I think players of both games will generally appreciate the other. They both have realistic hardcore shooting action and gun modding systems so I'm planning on playing them both for years to come.
I'm very interested to see how much of a role vehicles play in this game. Vehicles can kind of ruin gameplay for me if they are too overpowered like they were in battlefield 3 and 4. I'm mainly a fan of infantry combat so as long as they keep that core infantry gameplay going I'll keep coming back to Insurgency!
The 'airstrike' stuff does kind of worry be a little. It always feels really cheap when you get killed by stuff like that in games. Especially if you are a class that can't do anything about it except for hide and wait for it to be over. Or even worse, have to depend on a teammate to take it out before you are safe. I feel like this could be really bad especially against more casual players. If one team has a bunch of seasoned players and the other doesn't it could end up making things even more unbalanced than they already were. I guess we'll all just have to wait and see. I'm really excited for this game, but I may end up avoid all the game modes with vehicles/airstrikes if it becomes a problem.
One last note. I think you should still have some game modes available for the people that like to play the modes with only one life per round. Like Ambush. I liked playing those occasionally, but my friends weren't fans so I didn't play them much.