Ok, here are screenshots of how I have organised my shortcuts so far.
I have them organised well enough for me to find items I am looking for but it is still something I am working on.
I do it regularly but don't spend too much time on it. Generally I have regular times where I feel like doing something but not making anything and that is when I look at what I have so far and organise them more
1 thing is I organise these in a way that suits me. These may or may not suit you but maybe it will help you to workout the organisation that suits you.
Another thing is I am 63 and I have a huge issue with remembering words, especially names. These names I use are suitable for me but I had to search a lot in google to remember many of them.
And if anyone else has ideas for organising iClone contents I would like to see them. Some of them might appeal to me and help me organise mine even better?
Geometrical Folder is where I organise all simple shapes
Special Effects Folder is where I was organising the partical effects but seriously thinking of separating them into the other folder
For example all rain particles moved into the Aerial folder because that's what they are related to.
Celestial Folder is for anything relating to space
Aerial Folder is for anything relating to the sky. Thinking about moving the planes, helicopters etc here too
All animals used to be in the characters folder but now all flying animals is in the Aerial Folder
Aquatics Folder is where I put anything to do with water. Animals in here are fish, sharks Dolphins etc. I also have Coastal which is everything relating to beaches including certain architecture.
One good thing about shortcuts is things like architecture can be used in so many places that organising the actual files is complex. By having shortcuts I can just copy them
and place them in as many folders as I want and they don't use up too much disk space. Also, if ever a content gets updated by its developer then providing the name remains
the same I can just replace the original with the new and all shortcuts to it will automatically use it.
Terrestrial Folder is for everything relating to nature including wild animals like Lions, Girrafes etc
Agricultural Folder is for everything relating to growing plants and animals for food or decorations
Urbanoidal Folder is for everything relating to cities, towns, villages etc
Interial Folder is for everything relating to inside buildings. The furniture folder is the primary place for furniture but certain furniture can also be used outside.
Copy theshorcuts that apply to that and put them wherever needed
Lighing Folder is for all lighting elements
Characters Folder is something I am still working on and trying to decide how to do it
Locations Folder is complete scenes and not just a single item for creating scenes

One thing I don't like is having too many sub folders. I find it difficult to remember which folders things are in when there are too many.
So I have been working on starting the name of the shortcut with name I used to have as a subfolder and have all the shortcuts in a single folder.
That way I can just look through all the shortcuts in that 1 folder to find what I am after and they are organised by the start name to help me find it. It also means I can
easily see other things and I might find something better than what I am looking for but had forgotten I had it.
For example these lights used to be in folders called Candles, Chandaliers, Flashlights, Flourescents, Lamps, Lanterns and Streets.
Now they are all in a single folder and added those folder names to the start of the shortcuts names.
i7-3770 3.4GHz CPU 16 GB Ram
GeForce GTX1080 TI 11GB
Windows 10 Pro 64bit