well if said 2 way is designed competently in more ways than its comparable "bigger" siblings, then yes they're a better use of your money. and there are many examples of that
There are a lot of ways to design a 2 way. As usual with audio, your preferences and the compromises of the speaker need to interplay a lot for you to reach satisfaction.
I can think of completely opposite 2 way solutions, reaching very different outcomes. Are you saying all 2 ways are always better for you? What are you saying?
This is my speaker, PranaFidelity Dhyana, a quasi line-array. Very easy to drive; it is designed to be a resistive rather than a reactive load. Nominal impedance is 8 Ohms, with the lowest dip being 6.1 Ohm at 172 Hz. Phase angles are very shallow. A comfortable load for my Octave tube power amp (ca. 80 W/ch into 8 Ohms).
I love its tone, liveliness and dynamics. It also has great resolution and a very pure sound -- the speaker is very low distortion including at high SPL.
The subwoofer (coming in at 40 Hz with a steep 24 dB/octave slope) only makes a subtle contribution to the music; the two-way goes pretty deep and it has a very strong mid-bass foundation.
I don't know if I could agree. 2way's cover a lot of ground. Stand mounts floor mounts, large format 15's and horns/waveguides. Are you going to allow 2 1/2 ways? A full range with a woofer or a tweeter added?