I'd really love to see the AI actively research maritime techs when it is stuck alone on tiny islands. Often, these lone AIs waste precious research on techs that are useless in their situation (such as military techs), and will navigate only very late...
In general, it would be nice if the AI science pattern would depend more of the environment (i.e offensive techs being researched if many neighbours are around, peacetime techs being researched if there is enough romm between foreign productive centers and the AI's own, maritime techs being researched if the accessible land is too small, etc.)
That would make the game much more interesting and challenging IMHO
