I'd never want a system that could only sound great with the best recordings. To that end I've always voiced my systems to sound GOOD with mediocre recordings since this is where the vast majority of music resides. As I and others have mentioned, get the timbre, tonality right and mediocre recordings can be involving, great recording simply follow along and become even more involving.
Mostly, I want my system to be musical, certainly I seek maximum resolution but not at the price of musical, I do believe these are not mutually exclusive goals.