Title pretty much says it all. Not sure if this has been suggested or not before but I figured I would make a post.
It would be cool to see the remaining elite diary items added and maybe adding bonuses similar to the ones already in the game, but to their own. (Specifically falador shield 4, kandarin headgear 4, mortyania legs 4, etc). For example, the current ones add skilling bonuses and experience bonuses. If new ones were added, it could be similar.
Whether this is added via achievement shop or some other way, it would be cool to see in the game. If it was through achievements, that would bring more content and things for players to do.
First suggestion, thanks