I don't know if this is a "tip" or a useful comment. but my opinion is that it depends a lot on what you want to create and the background of your character. Personally I prefer to use 2 colors, I have few costumes in which I use more than 2 colors
For exemple:
To hold the weapon like this you need to use a Broadsword, Mace or Axe and activate the + zoom option that is there in the middle of the screen ( In this case the image has a - symbol because the zoom is already activated)
This is the whole costume, but as it was just an idea I didn't finish it.
Ullr.costume
Well, to me its a very good costume! and its hard to create a good "plant based" costume, I really like the samurai and fighters theme, but these are the characters that I have few likes compared to others. I just wanted to say that sometimes people prefer different themes 😁