I would agree that measuring your room would be a great starting point. Jot done some notes on what you enjoy about the system and what you’d like to improve. Then as simple as some basic REW measurements with a Umik1 microphone and you’ll at least put a visual to what you can hear. Then you can start tinkering with placement configurations to verify if the cardas setup was best. Financial investment is about $100, but the measurement sweep noises are annoying. You’ll lose an afternoon real quick with your tinkering but the improvements cost you nothing.
As to changes in gear, I think low hanging fruit to try would be changing out some interconnects and tubes. I apologize if I missed what your current tubes are, but what are you currently running in there? With interconnects, check out Hapa Audio Ember series as a great jump up for a reasonable cost. Ember is the best bang for your buck I’ve found anywhere, but their Aero series is truely exceptional.
The fact you’re still looking to improve things further is what makes this hobby fun. Never a finished product as you can always tinker some more. ![]()

