OP, “$15K… 10 - 15% on speakers”.
Unlikely a well optimized system… but possible. I think you have to start with a thought about what you want to spend… and then audition and make decisions that balance and optimize the sound. About thirty years ago I found some extremely good sounding speakers… Apogee Slant 8’s that cost around 10% the cost of my whole system. The ribbons were simply stunning, particularly for the money. I had them for 15 years. They were not perfect… but they sounded well beyond their cost.
I eventually got speaker that are at the 25% range ($32K). There is no comparison… these are not in the same class. But you build a system one piece at a time… sometimes the proportions get extreme.