Hi @Henry and @janemc I think ThinkComposer can help you. It is in Beta testing but will be lauched before half year.
It support format coloring and even design your own node types (Definitions). No 3D-ish.
@Henry There will be multiple license types/editions, prices and discounts. The very basic, up to 50 Ideas (nodes+lines) will be free for non-commercial use.
@janemc When you click an Idea (either a Concept/Node or a Relationship/Line) you can see:
- A supertree of the Origins or "Pointed by" Ideas.
- A subtree of the Targets or "Pointing to" Ideas.
I hope you give it a try.
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