A good mindmap should be faithful to the surah, but also usable by the human memory that needs to carry it.
If you chase correctness in a purely academic way, the map can become too dense or too literal to function as a memory aid. If you chase intuition without discipline, the map can become personally satisfying but structurally misleading.
Part of the beauty of the Quran is that different people, with different styles of thinking, naturally notice different patterns in it. That is not a flaw in mindmapping. It is part of why personal mapping can work so well. The goal is not to erase that difference. The goal is to let the student benefit from personal intuitiveness without violating the actual flow, wording, and meaning of the surah.
So the balance is this: keep the text honest, keep the meaning honest, and then allow yourself to choose the branch structure, labels, and grouping style that makes the surah easier for you to carry. A map is not a tafsir replacement and it is not random art. It is a memory structure that should still respect the shape of the surah.