Move Alexander Stewart´s army towards Inverlochly and take it. Then move him on Dunstaffnage and Isle of Islay. Move all other expendable troops to Inverness and start cranking out pikes, highlanders and archers there. Convert all castles but Stirling and Inverlochly to settlements. I don´t convert Inverness until I have a 2nd full stack. Build ships asap to intecept the Norwegians. The ones produced on the west coast will ferry A.S over to take Islay.

Make shure all your ships are outside Wick when the Norse invasion comes and sink all their ships off coast. They will spawn a bit out to sea to the east of Wick. The king goes down and the only troops they have left is the ones they start with and a spawned stack on the Isle of Man which you will take last. Now your army in Inverness, can take Wick, Kirkwall, Stornoway, Skye, Mull, Arran and finally Castle town which will render a really good developed castle, the 3rd. It´s all you need. A.S will reinforce the south english border togehter with William Wallace.

I always tend to ally with the Irish and Welsh. Help them out as much as I can but usually I´m too late to help the succumbing Welsh. Only one major foe left - England. Once I flipped and allied with the English and took on the Welsh and Ireland and that worked well too.