It's been a while since I auditioned Thiel speakers and the one's I listened to may not have been the exact model you are looking to pair with an amplifier, but I remember how the highs produced by the one's I listened to were very detailed and with some of the amps at the showroom I did the audition at, to me they sounded a bit too bright. With the list of amps in your posting, I'd say the McIntosh is the one with the smoothest high end.
As for amplifier power output, I agree with what has been stated here, you can't have too much, but you certainly can have not enough.
As for amplifier power output, I agree with what has been stated here, you can't have too much, but you certainly can have not enough.