Obviously all parts of the system chain make a difference, but few make more difference than the speakers. Especially how they interact with the room and present a soundstage.
If you love the sound of the Electa Amator speakers, I’d look to get bigger tube amp. Even if it’s PP vs SET, there are some great sounding PP examples that would drive the Amator to the desired sound level.
On a side note - Not sure if you're running a sub, but a well setup pair of smallish active subs could be a nice pairing with your speakers/system.