My youngest son is extremely partial to Haggai as a name. Personally I like Jeremiah and James (which if I had had a third son would have been his name - Jeremiah James)
I've always like the name Calvin (as in Calvin and Hobbes).
We have 6 and 2 year old girls and they are great! It seems like they are easier to take care of than boys at their ages, but when they get older I will just have to show the young men the .38 and baseball bat!
Alexander is a pretty good name ("the Great" and "and the awful, horrible, no good, very bad day") but it is also pretty common right now. I have three friends with boys named Alexander, and for each it is their first born and only current child.
Have the middle name be something with two syllables so that when you are yelling at him you can pull out the full polysyllabic name and give it some weight. "Alexander Andreacus Kludge! You get in here right this minute!"