I played for some 60 turns today, and as promised, here's my first impression.
First off, I enjoyed playing very much. You have taken care of details and everything is well thought of. The increased movement of units (even more so on roads) just feels fine for the scale of time and map. The scripted events were nice, yet the cities in questions were to far off that I would have sent units there. Is there any bonus in for the one helping out?
I as well took Leon, mostly because I wanted to have Santiago de Compostela. I agree with Kidinnu that it seems a bit easy on noble level - keeping your cities happy and healthy is hardly a challenge. I would appreciate if the difficulty could be set freely.
I ran into some more difficulties than Kidinnu, though. I didn't want to go conquer cities before having siege weapons and so only did some cottage raids. Alfonso made peace with the Moors first. At a time they wouldn't even talk to me. His next move was to declare war on me. In the war with him, I neglected my defenses to the south and lost my southernmost town to the Moors. I relieved Alfonso of two cities though, and plan to "unite" Leon and Kastilia. Also I hope to have a great prophet soon, so that I can build my Cathedral in Santiago.
A few thoughts and suggestions:
a detail - renaissance starting on education seems a bit too early for me
If I recall history correctly, the occupation of some first cities on the mediterranean coast gave the spanish kingdoms some trade boost. Maybe this could be represented in the game with the possibility to trade with Venice for instance if you control any port on the southern half of the iberian half isle.
Maybe permanent alliances should be made possible, too? Defensive pacts don't seem to be too useful since war against the Moors is one of the main goals. I think historically Kastilia-Leon and Aragon entered such a permanent alliance later, forming early Spain.
Also I think that the question how to treat other faiths was one of the main political issues in these times. Both christians and moslems had phases of religious tolerance and zeal. Maybe this could be reflected by civics, one giving boons on having several religions in your cities, and others penalties (for which something has an inquisitor would be needed, to get rid off unwanted religions).
Finally, maybe 'liberating' some prestigious towns like Toledo, Granada or Cordoba as first christian nation should give some extra victory points?
All in all, the scenerio made a fabulous impression on me, and I will write some more when I am further into the game.
Oh... and a final question: Any particular reason why the map is flipped by 90 degrees?
the last that still tries to free the land 
