To answer your question - yes, it is okay, but your have to be very very careful in how you explain your framework. A major risk of doing so is being NOT MECE. Think about the "conceptual areas" you listed above. Okay, you put Competition under Volume. What about Price then? Does Competition affect Price too? If yes, do you write it again under Price? If you do so, is your framework still MECE? How do you explain it in a way that's MECE? If you cannot think of a good way to explain, I would advise against creating your framework such way.
If you are thinking about whether you can branch out from a mathematical/algebraic component into a list of qualitative/conceptual areas in general, yes you definitely can. There is no written rule. If this is the best way to approach a problem, definitely do so.
To answer the second part of your question, it is not always expected that you continue your framework with mathematical components, but very often that is the most logical and MECE way to divide up a problem. So try to do that if applicable.