I've got some suggestions which you might find useful:

Picture One:
In this case one can't pick up the glove because everytime you click the icon, the NPC gets active.
Picture Two:
Items like daggers, gloves, shirts etc. should be bundled like bug-legs for example.
Picture Three:
Seems theres an Error in the Map: One could move along the arrows.
The DOT shows a place, if when clicked on a dropped goodie one moves out of the cave instead of picking it up when clicked.
Picture Four:
Another Map Error: One can't move along this way.
Picture Five:
The blue bar should be on focus while selling items; would be easier for gameplay.
Other Suggestions:
It would be nice if you would implement the function to find out in which map other players are with a console function e.g. "/find Player1"
Also a Teleporter from map to map would be nice (like in Zelda etc.)
So, thats it for now.
Perhaps someone would take the chance to continue this list.
Greets,
blue