I don't know if there is a mechanic that you can turn on in character config that shows the radius of your own spells or not. If it doesn't exist then it should be added to help us healers with judging distance. It's challenging (for me at least) to judge the radius of a 6y heal while in the heat of battle. Using Med II on final boss would cause the adds to come right after me and put unnecessary stress on my tank (which I apologize to btw). Again I figured the reduction on HoT pot. would make it work differently but it is still producing aggro issues if used incorrectly (which I did use it incorrectly).