My main system for 10 yrs. was a Sony HTIB that came with Sony SS-U2000 bookshelves (8" two-way), a center (two 3-1/2" mids), a pair of cube (3-1/2" mids) rears, and an STR-DG125 receiver. My first upgrade purchase was to change the receiver to a Marantz SR-5001; just by doing that the Sony POS speakers took a different sound, better SQ. That's what made me start looking for speakers, until I decided for my current set.
I see that you pulled the trigger on the Dali, so this comment might be pointless, but your Epos were a good set of speakers, by changing the Sony to an Arcam or a similar amp/receiver SQ would have improved dramatically.