Questioning the unquestionable: Koa phonology

A crazy idea hit me out of the blue a couple days ago. Or actually, as it turns out, maybe not so crazy, but it certainly seemed that way at the time. By way of background, let me quickly sketch out the (simplified) consonant phoneme inventories of a bunch of languages with small phonologies...

Pirahã: p t ' m n s h

Hawaiian: p k ' m n l h w

Samoan: p t ' m n ŋ l f s v

Blackfoot: p t k m n s h w y

Plains Cree: p t c k m n s w y

Aita Rotokas: p t k m n ŋ r β ɣ

Maori: p t k m n ŋ r f h w

Kiribati: p pɣ t k mɣ n ŋ r β βɣ

Tongan: p t k ' m n ŋ l f s h v

Arapaho: b t č k ' n θ s x h w y

Ainu: p t č k ' m n r s h w y

Cheyenne: p t k ' m n s š x h v

Comanche: p t k ' m n r s h β w y

Finnish: p t d k ' m n ŋ l r s h v y

Bemba: p t č k m n ŋ l f β s w y

Ojibwe: p t č k m n l r f s š ð y w

Inuktitut: p t k q m n ŋ l r s ł v ɣ y

Cherokee: t d ts tl k g kw m n l s h w y

Bislama: p t č k m n ŋ l r f v s h w y

Cebuano: p b t d k g ' m n ŋ r l s h w y

Tagalog: p b t d k g ' m n ñ ŋ l r s h w y

Japanese: p b t d č j k g m n r s z h (w) y

Hittite: p b t d ts k g kw gw m n r l s x h w y

And now, Koa: p t k ' m n l s h

I was really surprised to realize that Koa is conspicuous in the company of these other languages. Exotic, even: along with Pirahã, it is the only language to lack any kind of highly sonorant voiced labial consonant. (It's also somewhat unusual in lacking /y/, but I'm leaving that aside for the moment because (1) Koa does sort of have it in words like ia, and (2) it's not quite as universal.)

So what to do about this? Obviously /w/ has tried to make it into Koa on numerous occasions in the past, and was finally permanently rejected a couple years ago. The thing is, though, that it was always in the company of /y/, and I always conceptualized it as an invariant [w], both of which doomed it for various reasons.

Picturing a putative incoming phoneme as /v/ is really different. It wouldn't need to have all those distribution restrictions: it could pattern just like any other consonant. It could have acceptable variant pronunciations from [v] to [β] to [w], making it accessible to speakers of nearly every language on Earth.* And because its ideal form is still consonantal rather than vocalic, it preserves the overall "feel" of Koa, rather than making it feel all sloppy and amorphous like it was with /y/ and /w/.

It seems, then, like it wouldn't be at all unrealistic to add /v/ to Koa. I'd finally recoup the loss of forms from the departure of /c/ -- 5 particles and 500 roots. I'm kind of terrified of the idea, as it would be a tremendous change, and with so much being created right now, if I work /v/ into things it might be difficult to extricate it if I change my mind later. On the other hand, looking at all those inventories up there, it seems more like the question should be why on Earth not to add it.

I have two possible reasons. One is that, for speakers that pronounce /v/ as [w], we get into some of the same problems of ambiguity that we were grappling with way back when with the other semivowels: mova and moa both end up as [moa], etc. The thing is that (1) like Amelia points out, languages cope with way more homophones than this with absolutely no trouble, and (2) Allison is totally right that the advantages are likely to massively outweigh the disadvantages.

More seriously, I'm really happy with my usitative particle, ua, and I would have to give that up if I were bringing va on board. The grief might be too great to bear. Of course, I could always be idiosyncratic and just use ua instead of va. Hm.

Anyway, this decision is far from being made at this point, but it's certainly looking increasingly likely.

*There are exceptions. Bengali seems to have nothing in this neighborhood and would probably have to resort to [b]. Some other languages like Basque, Catalan and Japanese are kind of marginal, but have similar enough sounds that they could probably pull it off. In any event, it's no worse than /h/ in terms of cross-linguistic universality.