Kamaka ukuleles are the most consistent from size to size. If I were going to score their instruments, each size would score similarly.
KoAloha ukuleles sound better on the smaller end of the spectrum. Their tenors sound great, but they really shine with their sopranos and concerts.
Kanile'a ukuleles sound better on the larger end of the spectrum. Their tenors, super-tenors, baritones, and guileles are where their quality really shows.
I don't have much experience with Ko'olau, if you're even counting them, but Ko'olau sopranos are pretty rare, and I've never played one. If Pono ukuleles are any indication, they're pretty consistent in sizes, like Kamaka.
Based on all that, for me, KoAloha and Kamaka are the way to go with smaller sizes. I like the Kamaka sound, but once I got a Kamaka in a bigger size, I had little desire to get one of their sopranos. On the other hand, one nit-pick I have about KoAloha (and Opio and Rebel) ukuleles is that their sopranos don't have frets beyond the 12th. Their fretboard extends past the neck, but no frets. As someone who plays songs that occasionally go past the 12th fret, this is a bit annoying.