I think it would be easier to just accept that "model" already means "simplified description" (source https://en.oxforddictionaries.com/definition/model https:/

I think it would be easier to just accept that "model" already means "simplified description" (source https://en.oxforddictionaries.com/definition/model https://en.oxforddictionaries.com/definition/model) and use another word to refer to the superset you're mentioning. That's because language is mostly useful for communication between people, here and now. Treating a natural language as a construct to refine until it reaches a mathematical beauty where nice and short words mean what they "should mean" often causes so much grief and wasted energy.