TimK, you can put Spendor SP range and Harbeth in your shortlist if you are looking for natural midrange with smooth highs and low listening fatigue. Both these speakers have BBC heritage and sound quite close although not exactly similar. Used Spendors may be cheaper than the equivalent Harbeths. The advantage of the Harbeth and Spendor is they are easy to drive and don't require high powered amplifiers. A good quality integrated which is able to provide a decent amount of current will be more than sufficient.
Another speaker with less piercing highs is Sonus Faber. My experience with the older Cremona range and Grand Piano reveals these to be even more rolled off in the highs than the Harbeth as if a blanket is covering these speakers. The midrange and clarity isn't as good as the Harbeth and the sound is quite colored. The higher SF models(Guarneri Homage upwards) are better in this regard.
There may be other speakers that fit the bill. Others can probably recommend.
Another speaker with less piercing highs is Sonus Faber. My experience with the older Cremona range and Grand Piano reveals these to be even more rolled off in the highs than the Harbeth as if a blanket is covering these speakers. The midrange and clarity isn't as good as the Harbeth and the sound is quite colored. The higher SF models(Guarneri Homage upwards) are better in this regard.
There may be other speakers that fit the bill. Others can probably recommend.