Even if there was an ideal ratio at one price point there's no reason to think it'd hold at another one. The points of diminishing returns for various types of components aren't going to all be in the same ballpark. People will fight about what they are like everything else but I'd say the point of diminishing returns for speakers can be much higher than for other components. It's not to say that speakers get better as
In my opinion, the most important things are the speakers and how they interact with the room. Second is having enough power. Source, preamp and amplifier quality are all factors but considerably less significant to the overall sound. I find differences in cables to generally be below my threshold of interest. The thing that a lot of people ignore is the room and that makes a far bigger difference than cables or electronics in most cases.
In my opinion, the most important things are the speakers and how they interact with the room. Second is having enough power. Source, preamp and amplifier quality are all factors but considerably less significant to the overall sound. I find differences in cables to generally be below my threshold of interest. The thing that a lot of people ignore is the room and that makes a far bigger difference than cables or electronics in most cases.