I just finished a game with Spain (Monarch, latest SVN, 1075 or something like that):
it still feels like a bonus game

Spain is just awesome. By 1648 I had 18 colonies - no one else had even 1, I could have built more, but my research was to slow (and I had levees + protestantism everywhere by 1600^^). From the time I spawned until the historical victory I only lost out to 2 wonders (and one was my own stupidity^^)
I think the balancing Spain vs Cordoba is fine and also Spain vs Portugal seemed ok, maybe Portugal could do with 1-2 more units as they now start at war with a potentially strong Cordoba but I think it's okay.
The only minor nitpicks are:
- Barcelona revolted and tried to gain independe
while I had a stability of 67, 5-6 turns before the game ended. I know these minor civs and their revolutions are in some way realistic but come on...stability 67 and they still try? and if they succeed I lose my 2nd (+3rd) cultural expansion + a lot of buildings...can't these revolts be limited to stability values lower than lets say 10 or maybe 20? (that should account for 80% of all game-situations apart from the ones close to the end)
- the other civs didn't really try to found protestantism. The first one to research Printing Press was (of course) Germany - around 1600, so if I hadn't researched it in the 1520s the Dutch would have founded Protestantism again.
Maybe there is some way to give the AI some sort of incentive to research it after 1500? because my research doubles during the time from 1490 to 1530 when I spread protestantism while the AI doesn't use this awesome boost.
edit:
to clarify: when playing with Cordoba you can usually easily rush Spain and destroy them. When playing with Spain you can usually take 2-4 of Cordobas cities. Sue for peace, wait untill you get armored lancers and then take the rest of Iberia. By 1050 you can easily own Iberia.
So while there is some room for "buffing the opposing site" both are able to kill the other when played by a human player. And when it's AI vs AI, usually Spain wins in ~40-50% of the games and in the others owns roughly half the pensinula which seems fine to me.
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My first recommendation for a beginner is Venice but once you have gotten to know this great mod a little, go and try Spain.
You start conquering, then settling in peace untill Portugal spawns (which obviously is an insult to your greatness, so they have to die) and then you own a rich land and can go build wonders and colonies as much as you want. If you take some minor civs as vasalls you usually also get into some fights with France/England/Germany after 1450, so that you don't feel like you're playing simcity. It really feels like Civ in godmode
