Looking for speakers to match with NAD S100/S200

I own a NAD S100/S200/S500 connected with Nordost Blues Heaven cables. I use this to drive a pair of B&W 604S3. Not very convinced with the speakers, i'd like to upgrade. Any suggestion? B&W 804S, KEF 203... open to any suggestion.
Found with an NAD 370 integrated that Paradigm Studio 60s or Studio 100s are good matchs - had the 60s in my system - both are class B rated speakers