Upgrade sugestion please


So i have a pair of paradigm studio 20v5(sealed),separate around 2 inches from the back wall(is all as possible) matched with a martin Logan sub(sealed), my room is around 11x21x,10 and is a bright room. I like most of the presentation except for the highs which are a bit grainy and bright. I tried the signature s2v3 in my room ,although it was too bright, I love how clean it was the beryllium tweeter.
so basically I am looking to eliminate the harsh and sibilance sound on my next speakers. Don’t care too much on bass because the sub will handle them.
So based on reviews and forums I think that the atc scm 7v3 is the solution, but I wonder if the Kef would be a better choice (livelier, funnier)
My fears from each one are:
Atc,: maybe too laid back? Less detail compared with the paradigm?lesser live presentation, image, ,?
Kef: is an aluminum tweeter as the paradigm! Probably not as clean as I want ? Less clean than the atc?
As a reference I have heard some totems the dreamcatcher, the hawk , too bright for me, the element line was great tough, but out of my budget, and for me it doesn’t worth those price anyway.
So please I need opinions from people have experience with them.
Btw I will improve to a emotiva a300 amplifier in any case. (Considering also the parasound a23 and nuprime sta9)
Thanks!!

128x128alfau7
I’ve never had any problem with any type of music including rock. I am not aware of this metallic sound that you are describing.
Another nice speaker that I have owned is the Spendor 3/5r2,which is a little more laid back than the Harbeth.
http://www.spendoraudio.com/HTML/S35R2_main.html
alfau7-

consider a pair of B&W 805 speakers. The Parasound a23 would make a very fine upgrade.
Thanks for your comments, right now I'm using a parasound zamp v3, I think is a balanced amp just not enough current for an atc or kef ls 50  I think
yogiboy, are you using a sub with the Harbeths? Do you think they make decent bass on their own if placed near room corners, of course on stands?
Kalali,
I tried a few subs.I like them better without them.  I find the bass is outstanding on these little guys.