This route is from 3 years ago, but is still applicable as a starting point for Pre-New Dawn update runs.

The current fastest route is going to Ibolhomen church and then straight to Salthamn for The Home Team mission. Once you've gotten that, go interact with the main Vesslan door and then kill the seeker and two runners for the barcodes. Place the radio from the start of the Home Team mission outside the bunker for later. Then do the rest of the bunker as normal but once you receive the missions, try get the runners to kill you and then warp to a random safe house and then to the radio you've placed down. Now run to the calling for help mission, avoiding the hunter spawn on the way. Now do Calling for Help as normal except if the enemies don't spawn, quickly join and leave a multiplayer game and they should be back. Then continue across the main bridge near Hastvik and get the safehouse in the church. Run towards Over and Out and do that as normal. Once you've done it, commit suicide and spawn back at the church. Now for a long bike ride along the main roads until you reach the mountain region. Grab the safehouse with the plane bunker by there and run up the mountain grabbing the Ruselburg safehouse by the Uttern Bunker. Do the bunker as normal, killing the runners outside for the barcodes. Fast travel to Ruselburg and run to the radio tower and do Radio Silence there. Now run all the way to Alby Church, getting the safehouse at Boo on the way. It's quicker to do this without a bike and just run across the fields. Go do hermelinen bunker as normal. Fast travel back to Alby Church and do Science of Deduction and Empty Spaces as usual. Fast travel back to Alby church and do Loud and Clear and then run to Skvarden, do it and then do Line of Fire. This should give you Enemy of my Enemy, so do that and then fast travel to Alby church. Run to the FOA facility and finish the run by doing the Behind the Curtain mission.