When you're organized and intelligent, you face one big downfall - you expect to be smart about everything. You do your homework, you plan, you think through things. You go through worst-case-scenarios for each step of the way. Put two such people together, and you both expect to cover all the bases. It usually works - but not for weddings.
There's nothing wrong with having dreams and goals for yourself or your family - in fact, it's important. The best way to actually realize those goals, though, is to make some kind of concrete plan with steps you can follow to help you realize the end result.