The Scots when controlled by the AI tend to survive in my experience but hardly ever expand by more than 1 or 2 provinces. The reason being it's imperative that the Scots expand very quickly otherwise they will simply go bankrupt or the English will become to powerful.

My most recent game as the Scots though has been a triumph so far, I believe the Scots have a great starting position, Inverness, Dublin, York and even Canaevon (sp?) can be swiftly occupied. The key is to steamroll the English before they have the chance to build up advanced units in England itself, I was able to conquer all of the rebel territories in Britain, reducing the English to Nottingham and London, thus badly stunting their growth. The English made early attempts on Canaevon and York but failed.

With an advanced army I was able to defeat the spear dominated English armies, take Nottingham and move onto London before the English could build up large armies. I ended up losing 800 men storming London which had a large garrison, i'd moved so fast that I was unable to develop siege equipment so had to storm as small english armies where starting to unite around me.

Once London fell I was rather rich and the English immediately sued for peace which I accepted. The problem that arises then is that because I was in close contact with the continent which I did not want to get involved with, the council of nobles immediately gave me missions in France and was eventually pulled into a major war in Europe.

Overall i've found the Scots to be a good all round faction, battles can be quite expensive in terms of causalties, but they are still strong which has pleasantly suprised me.

My favourite faction is still Milan at the moment though.