Formal:
* Cogitation: This implies a deep and deliberate process of thinking.
* Contemplation: Similar to cogitation, but often with a more meditative or reflective aspect.
* Formulation: This emphasizes the process of shaping and structuring the ideas.
* Conceptualization: This refers to the formation of abstract ideas.
Informal:
* Thoughts: This is a general term for ideas, but it doesn't necessarily imply organization.
* Brainstorming: This suggests a more spontaneous and less organized process of generating ideas.
* Mental draft: This specifically refers to a preliminary version of an idea, but it may not be fully organized.
* Inner monologue: This refers to the running commentary in your head, which may or may not be organized.
Figurative:
* Seed of an idea: This metaphor suggests potential for growth and development.
* Unspoken truths: This emphasizes the importance and power of unspoken ideas.
* The unsaid: This refers to things that are not explicitly stated but may be understood.
The best word for your specific situation depends on the context and the nuance you want to convey.