I gave SC another try as the allies yesterday, and came up with an idea. I had tried to show some aggressivenes by counterattacking into southern Germany or a naval invasion of northern Germany, and both ended with little gain and much loss of life.
So, while holding on by my fingernails in France, I invaded Norway straight away, using the 2 corps in the UK, Gen. Alexander as well as the Canadian Army. The Royal Navy and Bomber command gave support.
Smashing the Kriegsmarine was no problem at all, and my troops landed around Oslo. The city was quickly surrounded and repeatedly attacked, yet I couldn't quite defeat the german defenders. Then, the Germans broke through the Maginot line, threatening Paris - France was doomed. Therefore I operationally moved the BEF to Brest and navally moved it to Norway.
Oslo was finally taken by 2 armies and 2 corps & HQ. Taking the western town (Bergen, I think), then was easy.
In my opinion, this is an interesting tactic for the Brits. The biggest advantage: you get quite a few MPPs and take away from Germany's, while Germany can't (and won't) do much to stop you, save reinforcing it's corps. Also, your units gain some experience. Of course, it also makes the battle of France harder for you, so it comes down to a judgement call.
Strategic advantages are limited: It makes a german invasion of Sweden much harder, and makes an allied invasion of that country possible. It probably is not much good for as a base for attacks on the german mainland.
One question I have is this: On taking Oslo, I got the message "Allies liberate Norway". This had no influence whatsoever on the map, the German corps in Bergen was still there. So is there anything behind that message save "flavour"?
One thing I don't like is the placement of port hexes. They make shore bombardment on some cities much more difficult, if not impossible - and for no apparent reason. Why make an extra hex where naval movement is prohibited? Wouldn't it be possible to make port-cities where land units could be directly placed (and then attacked by sea)?