You're not gonna get much in terms of upgrades with gold. You will get increased mileage earning as well as a free checked bag, free MCE at T-24 subject to availability, free baggage, and early boarding.
Other than the MCE and mileage, these benefits can be had with an AA cobrand credit card, along with the bonus miles that come with that card (I believe the Citi card is offering 50k right now).
Seeing as you don't fly often enough to make gold this year, unless those plans are changing in the next year I wouldn't advise it.