Yamaha Amp Upgrade Suggestions?

Hi,
I'm looking to upgrade my Amp in the setup below, It does sound very clear but it also lacks a bit musically.

It was great for Suround use but I'm not using that setup anymore.

Had an Arcam A65 recomended, this is the sort of price range and intergrated or a pre power if I think it would make a difference.

The Arcam also has a switched second set of speakers which would be usefull for another room

What would sound best, or would it not make much difference to this setup

Rooms about 4m x 4m

Music varies Reggae, Funk and Rock, no classical or Jazz


Yamaha kx 493 CD Player
Sansui TU 717 Tuner
Cambridge DAB 300
Yamaha DSP A5 Amp (also 5.1)
Cambridge Interconnects
Kef Q1's Biwired

Thanks

Gildas