If he's the "king of the roost", he's probably just expending a lot more energy than the other new ones making sure they know that. Angels can have very singular personalities like any other cichlid and that can make one more sedate, aggressive, big eater etc. I think you're fine from what you've posted. Not knowing what the relative sizes are for all 7, keep in mind that aggression can become an issue in that size tank. It may not manifest itself at all, but it's a good possibility as they all settle into the space. And that space may end being a little tight for all 7 at some point for them to grow to proper size and shape.
"Why can't my wife see all of this stuff as an investment?"