We do have an upcoming audio meet planned in April. I will certainly get this played over there in front of some more ears. Will post thr outcome soon.Just a thought, have you tried a different and /or speakers to see if they interact differently ?
Not received any tube suggestions here, yet, I do not think any drastic improvement or change is required, rather so tweaks including the suggested mods and tubes which are easier done by a not so comfortable diyer like me.Don't know how to help further. You've got good tubes already, can't say any more 'rolling' will change the sound appreciably.