Agree that Capital Conquest needs to be fixed. If your turn is toward the end, it is ridiculously easy to lose your capital in the first round even if you place it on the territory with your largest army.
I would not make it so you cannot attack a capital the first turn.
What I would do is have the capital placement come with a 2 troop bonus on that territory, and get rid of the bonus you normally get for holding your capital on the first turn.
There is another major flaw, too: The game description is factually inaccurate. It says "conquer and defend" all capitals to win the game. If this were true, you would not need to simply conquer all the capitals to win, you would also need to hold all the capitals until your next turn.