It is more realistic in terms of how the AI behave.
Red air is pretty heavy at the start and the Sams wait until you trespass further into their zones before targeting you. Don't forget about other stand off weapons like JSOWs and SBDs.
In MP we generally have pilots firing HARMs at the SAM sites while others ingress with SBD/JSOWs while the SAMs are suppressed. You should be able to do this as well with the AI pilots in your flight by giving them Harms and ordering them to attack your target while you ingress on the SAM sites. We are able to take down SA-10s in OP. Bear Trap using this technique.
You need to re-think your tactics a bit which almost makes this latest update a whole new ball game.
When you wear down the Red side a bit you can start using some of your old tactics again, but the AD has gotten smarter about turning on and off radar, so you gotta give 'em a little more respect now. Also the Red air AI will split up on you and get you in a pincer if you aren't careful.
There is no shame in aborting if things don't go as planned. You can always refuel and make a second run as well if things go awry on the first run.
Have fun learning new techniques and don't worry too much about the log book or rank ATM.