First, despite its surprisingly intricate ordering rules, I don't think there's any motivation to think of Koa as agglutinative, or of sequences of particles and predicates at the same syntactic node as necessarily being single "words." Given (A) that pauses between particles modifying a given head are allowed, and (B) that many or even most such particles also exist as "words" independent of that syntax, characterizing them as affixes would require some awkward and unparsimonious assertions.
Taking ni "I/me/my," for example, we can find this in verb-initial position (ninae "I see"), verb-final position (tanáeni "she sees me"), noun-initial position (nimama "my mother"), noun-final position (táloni "my house"), with adjunct particles (laní or la ni "to me"), and independently when focalized/fronted (ni sa éteta "It was I who did it"). I'm not sure how productive it would be to classify the chunk of phonetic material [ni] as constituting different words or affixes in these six syntactic positions; it seems better to say that the particle ni may appear in all these positions, with particular effects.
Secondly, I think I took the joining of particles with their heads past the point of both need and aesthetics. Many resulting words are needlessly long; but perhaps more importantly, I just don't like certain combinations. Articles, for example, have never stopped looking dumb to me when mooshed onto their nouns.
Here, then, are the rearticulated and somewhat moderated principles of word break conventions as I'm currently thinking of them.
2. Preposed particles whose scope is an unarticled predicate, and postposed particles under all circumstances, are written together with that predicate regardless of how complex it is. This may require the use of additional accentuation where pronouns and directionals are suffixed to the root.
lakoto = "homewards"
nisánota la ko mutulu ka kúmumani = "I said it to make my teacher angry"
3. Independent complexes of particles which do not include pronouns are written together (nahua "nothing," puiá "that's what they say!").
ko koutusi = "bookbuying"
5. Conventions for particle complexes including pronouns (la + ni "to me," nahu + nu "none of us") are still under consideration.
6. In all other cases, particles are written independently.
The text referenced in the earlier post on word-break conventions would now look like this:
Talai la ka ásulota la ko vúakupu e ko mivami, sii, tamene la ko kóuva e tule lai la ni. Nisivima poli lo ko pato ve hua i cumisucu, ala helopu poka i pea pono e ka lílani sai i sikali. E ka tana i kali i koe ka sena. Hala kehe nulunike la ko mova ka kecu, ka nuluete la ko mupea ka háotenu nekene koa.
I have to say I like that a whole lot. It feels like a really nice balance between the traditional look and feel of Koa and the legibility advantages of grouping particles with their predicates.
We do still need to make a decision on point 5 above: between laní/la ni, nahunú/nahu nu and the like. For the moment I'm leaning towards separating the pronouns as I did in the excerpt, but I'll play with them in actual usage and see if that sticks.