Sure, but perhaps the development of the Scandinavian languages would be closer to the most likely outcome (speculation), with their general European influences

Sure, but perhaps the development of the Scandinavian languages would be closer to the most likely outcome (speculation), with their general European influences, rather than the wider, and better preserved Nordic variants. There's a brief comparison of Old Norse and Old English in the blog post mentioned, if interested. They were very similar, almost mutually intelligible, and so only major outside influences would have caused their divergence (as has happened). Without those influences, though, who knows, maybe Icelanders and the Germanic-British could still converse in their own tongues.