rescalable interface (not just resizable parts, also rescalable as in resolution)
being in 2 friendschats at once
guest clan chat in lobby
inviting new members , not by going to them, but via a system accessable from everywhere
if you turn off assist messages in global chat, but you have them turned on in another chat like the trade chat, the clickable assist doesnt work (bc its not turned on in global)
add interface parts in the map area, so it becomes a folder for different interfaces (example: drag your inventory onto the map, so you can switch between seeing the map or inv)
for example a search bar interface , to search anything, then a link to the wiki (instead of !wiki (name)) - this way you can actually search for something instead of already knowing what youre searching
better friends system - maybe even with friends requests, this way you know who adds you, or wants to be your friend
better notes interface, what the hell even is that that we have, most inconvenient notepad ever
change fonts/size of text (not for the whole game, but for the chats atleast..)
ingame runemetrics (the one from the rs website) where you can see your playtime, and all the other options in a good interface.
exp drops for after 200m (i think you dont get exp drops, could be wrong)
better follow system, why is it a magnet to a different person, instead of following the other persons actual path..
an actual currency that is worth 1000gp each or something, like in osrs. this way you can go over max cash by not using spirit shards (which are only accepted for trading rares)
offline messaging, like a personal email for friends in your friendslist. - when they come online, they have an inbox