I understand how big is your responsibility trying to make everyone happy.
About the subcategories..... If you wanna use subcategories, you will be using them, otherwise you will be using only the categories.
For example: The category Golf Courses doesn't need subcategories, The category Night Clubs doesn't need subcategories. The use of subcategories is not mandatory, it's optional just in case we need to use them. The subcategory creation should be an option inside the actual created categories.
The option to add a hotspot to multiple categories is not mandatory, it's optional. If someone needs to use, then, they can use it, other wise not. When you are creating a hotspot should be an option asking: Do you wanna post it in another category? If the answer is yes, a category selector is popping up, and the question will be moved to the next line just in case we wanna add the hotspot to another category.
Right now, if i wanna see only the icons from the categories, i just click on the icon Minimize category selection area, and if i want to revert the process, I just click on the icon Categories Views. You should create a section to select how to see the category section by default, and keep the actual icon to switch between views, just in case whoever is seeing the map wanna change the view of the category section. In that way everyone will be happy.
You are doing a great job here, and whatever you implement in the next version, it will be more than welcome.
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