Make Hero Challenges linkable via [shift+click], just like PoI and WPs.
Put the names of the challenges on the maps as mouse-over text.
Currently, people say “anyone for [insert name] HP” or “please help at [insert HP]”. The problem is that unless you are intimately familiar with the map, you won’t know to which HP they are referring, let alone where it is.
John Smith: “you should kill monsters, because killing monsters is awesome.”