You need to look more systematically at the little things in the system.
First cables can make a huge difference so can power conditioning.
The Ayre preamp isn't particularly warm, if the speakers are doing things yo like you need to address why there are things present in the system that are not, PMC speakers are accurate, they are not bright or sibilant, however, if the speakers are being overdriven, not enough power, or you are using cables which are not good or good enough which might excerbate the problem.
I would not change the speakers I would:
Change to a tube preamp, a Cary or CJ
Look at replacing or upgrading your cables
Adding a power conditioner.
First cables can make a huge difference so can power conditioning.
The Ayre preamp isn't particularly warm, if the speakers are doing things yo like you need to address why there are things present in the system that are not, PMC speakers are accurate, they are not bright or sibilant, however, if the speakers are being overdriven, not enough power, or you are using cables which are not good or good enough which might excerbate the problem.
I would not change the speakers I would:
Change to a tube preamp, a Cary or CJ
Look at replacing or upgrading your cables
Adding a power conditioner.