Don’t let others tell you that your system is not good. Unless anything there needs a recap or new wiring, then leave it alone. I mean, speakers maybe? But only if they’re in need of some service. But those a5’s are supposed to be great speakers (I’m a Spendor fan so I’m definitely biased!). Positioning and room treatment (if you haven’t already used some) is just as important as your components. Make sure you get a handle on the peak frequencies in your room and first reflections if you haven’t already done so.
Other than that, yeah…a nicer power strip/conditioner would be advisable. At least a high current Chang Lightspeed, or a Puritan if you can swing it. You also do not have to pay a great deal for some well made/shielded high current power cables as well. You’d be amazed at the difference that alone can make for the system.
If you’re itching to change at least one component, others here mentioned purchasing a nice outboard dac and I’d have to agree that would be a fun and noticeable improvement. Holo Audio Cyan 2 is affordable but hits way above its class.