Great Job! If you want to do it faster, remember that the AI sucks at defense, so the quicker you get into his territory the better.
Also, and this is kind of an exploit, notice what the AI up against S Svarlsbard did. Just built up every turn til he could overwhelm it. The AI will do that against your abandons at the expense of doing ANYTHING else. Essentially takes out one of the AI team for turns and turns if you make your abandon big enough. USE IT!
But like I said, good job.