I really feel like this thread has already got to be going somewhere and I just can't find it, but in case I'm wrong I'd like to start it and hear some people's opinions.
What are some effects you think should replace the XP bonuses on Heirlooms?
The first obvious thing that came to my mind was 5% movement speed on legs. Maybe there's concern about people using that to facilitate farming, but at the very least this can expire after the last scalable level just like the XP bonus would.
P.S. This isn't about whether or not you like the change, just what you'd replace the XP bonus with.