Wish it was practical to get rid of the transistors in both of my systems. The first transistor, by the way, was invented in 1947. The idea for the active devices you cherish is 70 years old. On the other hand, tubes go way back before the 1930s, even longer ago than what you wrote above. Probably the vacuum tube is more like 100 years old. The triode is inherently more linear than any transistor. This is not a matter of opinion. The age of the technology has nothing to do with it.
Do you really think that your system with 3 or 4 (not sure which) passive crossovers in the signal path is ever going to be optimal? What's better, no capacitor in the signal path or several very excellent capacitors (and resistors and inductors, required in order to achieve those steep slopes)? For me, the answer is "no capacitor". It's no wonder to me that you require a solid state amplifier to drive the complex and energy dissipating reactance of the crossover(s) you place between the amplifier and the speakers. What does the impedance curve look like? It must be a nightmare of low values, 2 ohms? 4 ohms? The question of what amplifier is optimal should never be decided out of context with the speaker to be mated with it, and you've created a monster that needs a high power solid state amplifier, to be sure. If you like it, that's fine. The whole world is wrong, and you are the only one who sees the light. Congratulations.