Putting aside the unlikely business class upgrade, if you're both on the same reservation you can get Main Cabin Extra seats right now by just selecting them on the seat map and paying the fee, which for a Gold is 1/2 price. They will be perfectly fine and less than $100 each way per person additional. You'll find it to be money well spent when you look behind you at the Main Cabin seating with less legroom. You may even be able to find some exit row seats with superb legroom.
Thanks again to everyone who replied for the info. I'm still a bit sour after paying USAirways (AA's predecessor) $149 for "Choice Seats" to/from Ireland a few years back. Turned out those seats were
exactly the same as regular coach seats, they just happened to be closer to the front. No extra legroom or better entertainment, food, attitude. What a waste. But AA says the MCE seats do have extra legroom, so maybe that will suffice. Thanks for explaining all the options.