The ability to create maps would be greatly enhanced by a more 'web 2.0'-ish map editor. Manually figuring out the coordinates is a slow process, and moving whole groups of objects around on a map takes way too much time.

'Drag and drop' map editing functionality would be a huge boon to the Zabbix maps function. It would also be nice to be able to group items together (the same effect as selecting multiple objects in Visio), so if I want to move 200 objects 50 pixels to the right, I can do so easily.