
Not to mention PVP buff server bonus (which can give you up to an additional 15% XP, AP and gold bonus).If you open the treasure map packs, they become bound (but you can put them in your bank).
Pledge of Mara is in game "marriage". You make a ring, and whenever you adventure with your partner when both of you have the ring equipped you get an additional 10% exp. This is additive (i.e. ESO+ Ring and Group bonus = 30% bonus exp)
Not to mention PVP buff server bonus (which can give you up to an additional 15% XP, AP and gold bonus).
So, with the Ring of Mara, ESO Plus, Group Bonus, PVP bonus, you'd end up with an almost 45% XP bonus.