Flexibility is the key value of separates.
Judging by $$$ alone is a poor way of going about it since $$$ is itself a really poor indicator of quality or performance.
Consider a favorite recipe for many is a colorful tube pre with a solid state amp. Pick the tube pre based on sound qualities you want to have and a solid state amp for the ability to drive difficult loads.
Having said that, I prefer to go with solid state integrateds and easy to drive speakers.