A good group of 4-6 would over all make note AP than a solo player into.Yes, by killing, doing bounty quests from the starting area, your alliance base, by capturing keeps or defending them ( the more enemies and time it takes the more rewarding) and also by repairing walls and gates.
If you're solo the AP is a lot higher
If you're zerging the AP is a lot lower
the ratio is up to you, if you can kill adequately as solo then thats more rewarding (if you can also avoid getting zerged)
All in all the golden section is a small group.