I find that listening to a full range of well recorded human voice (spoken word) is very revealing of colorations and crossover issues. If a speaker passes the test: you can make yourself believe you are listening to a live voice, it’s going to do well on all kinds of music.
For most speakers, I find, you know within 10 seconds you are listening to the kind kind of electronically reproduced voice that you could never confuse with a live person’s.
Also listening to the treble/soprano sections of naturally recorded choral music -- (Faure’s Requiem [Kings College Choir] I use often), or Paul Desmond’s sax on Time Out tracks, is very revealing of upper range crossover smoothness, and colorations.
Good speakers are revealing of less than perfect recordings. Music that can sound lively and sweet on cheaper speakers can sound un-engaging on really good speakers. But then listen to, say, Diana Krall’s "Walflower" and then you hear what you are paying for.
I had pair of ProAc EBS studios for about 30 years. Just sold those and now have an ATC set up. Very happy.