Ahhhhh ..... That is indeed unfortunate. It's a decent argument for staying with the hardware that you have. But, I think the original topic of this thread has been addressed. Use the STM32encode Library Linked in Post #4 to make working with the rotary encoder easier.
If you like, you can start a new thread asking for help with your NRF24L01 problems. You'll need to post a complete schematic, pictures of your wiring connections, and the results you get when using the code from Robin2's Tutorial. Using that code (that has worked for hundreds of people) will make debugging any hardware problems easier.
Finally, regarding your concerns about code size .... you can start another new thread. Post your complete code and your explanation as to why you think the size is a problem.