I've discussed (at least) four different types of reduplication in Koa over the years, but never written them down in one place or really thoroughly explored/documented what they should mean. Here are the types I've talked about so far:
1) Whole-word reduplication, normal stress on first element
kuma > kúmakuma
loe > lóeloe
ake > ákeake
Meaning: intensifier (very hot, very cold, very sharp)
Notes: We talked about this here near the bottom, only written as two separate words without clear intentions about stress...though I have to admit that when I read Ni loha loha se aloud I stress the second. Hm.
2) Reduplication minus onset, stress on second element
kuma > kumaúma
loe > loeóe
ake > akeláke (note L-insertion)
Meaning: affective/minimizing diminutive, "ish." (warmish, chilly, ...pointy? dunno). Minaína "gal."
Questions: (1) How is loeóe different from lóeki? (2) Is this too similar to the first type given the fact that they kind of have the opposite meaning? (3) Is that L-insertion -- the only thing saving the opposite of ákeake from basically and laughably being akeáke -- too ad-hoc?
3) First syllable, stress on full word
kuma > kukúma
loe > lolóe
ake > aáke (aháke?)
4) Reduplicate medial consonant with -a, stress on reduplicand
kuma > kumáma
loe > loáe
ake > akáke
Meaning: From here, "I was thinking this might serve to make the noun more euphemistic, more gentle, less objectionable, or something. So a pragmatic rather than semantic value."
Just for reference, here are the three sample words with each reduplication type in turn for comparison:
kúmakuma, kumaúma, kukúma, kumáma
lóeloe, loeóe, lolóe, loáe
ákeake, akeláke, aháke, akáke
This is going to require some thought, and maybe some study of what reduplication tends to be used for cross-linguistically. Just impressionistically, though:
* I don't like type 1 at all; as I alluded to before, my instinct is that these should sort of be separate words with the stress on the second one. Then, maybe weirdly, I feel like type 3 might be synonymous with type 1.
* If type 1 becomes separate words with stress on the second as I just suggested, type 2 kind of gets sabotaged. I always liked this one, though! Loeóe for "chilly" seems perfect...but on the other hand maybe lóeki really is enough here.
* Type 4 is really great for certain things (like luái) and I think it's valuable for a living language, though at the moment I'm not thinking of a lot of specific uses for it other than euphemisms. Could it also take on the meanings of type 2? I'm not sure. Thinking just of getting it on, I feel like there's an important difference between lúiki and luái!
Another thought I'm having here is that, just because a particular reduplication type technically has to be available for every word doesn't necessarily mean that it's going to be equally common with every word...so for example if mina mina means "a real woman" or whatever, and minaína means "gal," that doesn't have to entail that that type-2 strategy is now going to be used ALL the time and confuse everything.