I don't know how many of us use military symbols in our mapping. Of course Annual Volume 3 November 09 issue https://www.profantasy.com/annual/2009/november09.html has many and has the advantage of being integrated in CC3. It has a shortcoming (for me at least) of not being able to compose many of the symbols currently in use. It models "old" and "new" symbols defined in the US by MS2525 C/D and NATO APP 6 B/D. It provides the four types of units: Friendly/Blue, Enemy/Red, Unknown/Yellow, and Neutral/Green. Filled colors are limited to those, but for diagrams without a fill, there is a large selection. They can also be edited in some way in drawing programs.

The website is located here: https://spatialillusions.com/unitgenerator/

Attached is an example of some of my (incomplete) work using them.

I have not yet tried copying symbols from a separate document and pasting them into CC3. But they can be composed as *.png or *.svg which, by more skilled practitioners than I, can problem incorporate them into symbol catalogs.

So, when I look at your mesa just above, I can turn it into a mesa or canyon by switching my focus slightly.

MAKE IT STOP!!!!

Actually, no. It's this one. https://en.wikipedia.org/wiki/Saltstraumen

I like it. Here's one from Norway. Monsen may recognize it.

A little late. Your "swamp trees" reminded me of Spanish Moss which grows in the South-Eastern US and in the Gulf of Mexico and Caribbean. Once used as cushions in Model T's until Ford learned they had mites in them that made everyone itch, then they had to boil it. It's really not a moss. Apparently, its related to pineapple. Go figure.