First off, let's consider howtheduck's suggestion of having him talk about what it's like to have a dad that's cheating on his mother. This is too easy and too obvious a hook to be ignored so it says a lot about Lynn's paucity of imagination that she didn't go for the cotton candy. Watching an average kid try to read between the lines and figure out why his parents are angry and shouting all the time would be an excellent way of showing the human cost of being a cheating cheater who cheats. After all, Steve's need for glamour and excitement isn't just hurting Anne. He's got three kids at home he's messing up by chasing skirts and moaning that his wife doesn't understand his needs. Lynn could have and should have hammered that home. Jan Eliot does when she has Joan's asshole first husband go out of his way to not see what a selfish, churlish and immature shit-bird he looks like to everyone else.
We could also take a look at how well he gets on with the Enjo family since Dawn is about the same age as he is. While it's obvious that Lynn can not see the potential because of her inability to see the need for an Asian Girl Romance, seeing how he interacted with them would have added depth to his character that we didn't get. We also didn't get him telling Mike that he was talking out of his ass with "his brothers never fight" talk because he doesn't really like having to have Richard tagging along behind him much.
Finally, we didn't get to see what I really wanted to see: his reaction to having someone he sort of thought of as his special someone being chased after by some creepy zero who looked like they'd put Liz's dad in the wash and shrunk him. Having Chris try to warn Anthony off would have been a lot of wonderful dumb fun that Lynn just can't see.