Why adjustment to crossover point is significant change? It can be anywhere. But resulting frequency response matters. I mean what the difference in crossover point if frequency response is seamless? I do not see any crossover joint.
But from measurement point it is really interesting to know why sound of R3 Meta differs from original R3? Where is it on graphics? I mean real difference nor difference error or assumption.
What specific device do you use? I can't see buffer bypass or turning on directly. Maybe I need to be more attentive. Blue colored PCB.
I see Nord NC500 buffer.
Maybe you create another thread? I really want to read about R3 Meta measurements or even subjective review (not here) but from listeners. What if I would post weather forecast here?
There is no overkill looking at price of module. Also it overkill for everything. But it is suitable not only for R3 but for many things. Decide by your own.