You present a very rational explanation for selecting an amplifier "then" choosing an appropriate speaker match. I’ve done it either way over the years but discovered that at least for me deciding on the amplifier first proved to be most sucessful.
I also acknowledge that this option puts me in the distinct minority in the audiophile community but that’s okay with me. What you wrote mimics my thought process in beginning with the power amplifier. Again, most will find eventual success with either approach.
Charles