Good list
So why don't you think it will ever come? Don't think that the original CK sold enough to warrant a sequel? If that's the case, the developers could always take the idea behind CK and re-wrap it with a different name, additional features, and basically a newer experience.
The entire idea behind CK is a great one, it's one of the few games where I actually care about whats happening to my character and family. I like how the pyramid system basically works in it, you have the counts, then dukes, then kings/emperors. If your a high and mighty king you'll have to worry about diplomatic relations, rival armies, as well as keeping your vassals pleased so your kingdom doesn't come crashing down.
*Country selection screen should be as the Eu3 one,where you look around the world and the click on a nation to ply it, instead of having you select countries from a list.
This is something I wanted in the game too, it makes finding what you want to play a lot easier.
*Population number, it would really be interesting to see how many lived here and there at that time.
I like this idea, because it's another factor to consider when you wage war. If you create large armies and they are defeated, not only did you lose the battle, it has longer lasting effects.. such as less income from your provinces that you raised the army in because you just killed off a few thousand people that would otherwise be working and paying taxes.
I agree. The ability to blockade, warfare, and piracy come to mind. During these times you heard a lot about privateers who take advantage of wartime situations for their own ends. Your King is at war with France? Build a fleet and start looting. This could also impact your relations, say with Spain.. your working hard trying to have a relationship with that country and in the meantime one of your vassals is turning a hefty profit from pirating their ships.. but on the same token he's paying "extra" money per tax period. So you have to decide, more money or continuing to improve your relations with that country.
I was also thinking that adding suffix titles to your character would be nice if they excel for a long period at a specific thing, such as having tons of piety they might be known as Richard the Pious, or Richard the Blessed, and etc.
They could also add a system where you can "knight" people, but it takes a bit of prestige. Basically your transferring your prestige to a family member or court member who you find is valuable, and with that it may give them a slight bump in stats or something, make them more loyal, etc.
Possibly giving the game a more descriptive name so that people would more likely know what it is would be better too. Right now "Crusader Kings".. if I were to hear it without reading it, I would just think it had something to do with the Crusades, yet it feels more like the game is more based on your dyansty/family/people. If "Heir to the Throne" wasn't taken in another Paradox expansion, that would have been a good one.
Aside from the Pope declaring a crusade and you participating, there could be armies marching through europe, which could be a unit with a giant cross behind it, which takes a random path towards their destination. While their on the march, they gobble up resources, randomly pillage your land, reduce your county standing temporarily, reduce your population, etc. Even some of your advisors may take the call and leave. Also add the addition of islamic nations declaring a jihad which attack christian nations.