For sure it's different. AH is more like playing an arcade game. Fast paced etc. Il2 is more like a flight sim, flight modeling collisions etc.
So for the online stuff for me has been boring but I'm still learning too. My first 2 sorties I flew around and found nothing to fight. First one I deadsticked back to base because of a light fuel load. 2nd one I managed to land but got kicked on the runway for "inactivity" and I'll let you know how the 3rd one goes 
Of course most of that is down to the mission designer. You might try dabbling a bit in the editor to tweak something exactly to your tastes.
It's possible the enemy passed by and you didn't see them?
have you tried the time accel?
I wouldn't call AH an arcade. Any simulation has to make a design decision on where they draw the line and what they simulate and what they don't. AH decided not to include stuff like engine managements and IL2 and DCS did. It's not wrong, just drawing the line in a different place.
The FM for the pony in DCS felt ... something a little more dynamic and fluid. Can put my finger on why, but it was pretty close to AH. The fact I couldn't put my finger on it shows how close they are anyway. DCS is more of a study sim. They went hilt deep in fidelity and all the trouble of working the engine and all the little details. AH drew the line in a different place because they went for a broader approach of more planes that are pretty accurate, instead of fewer planes taken to a fetish level.
IL2 is somewhere in the middle.
I'd say that AH was like flying the most advance version of AW anyone ever dreamed of. IL2 and DCS are more like flying a scenario in AH with more engine managements. And I've had some long flights in a AH scenario where you didn't happen to be where the enemy tried to get through. War is Hell.
One thing to realize about DCS fidelity fetish (which can sometimes be frustrating), part of their revenue is providing low cost simulators to various militaries. Falcon 3.0 did that back in the day. They had special version they sold as low cost simulators to National Guards. So hyper fidelity is just going to be part of their brand and business model.
IL2 and AH are more like games. DCS is more like a military simulator that people are trying to play as a game, with varying levels of success.
