I'm not quite clear what the bold-face means; most of the words there are clearly content words (so maybe what I don't understand is what your content/function distinction is).
So, by cases.
I would think that 'a' was pretty much a contentless word; it is just an exclamation, without any meaning, though perhaps with some form of presentation (varying with the situation).
'ala' is a negation, so a (as we would say) syncategorematic term, one that reverses the truth value or the range of reference of that to which it is attached. It also functions as a noun, verb, modifier, and pronoun, at least -- and as an exclamation.
'ale/i' is also syncategorematic, a quantifier. It is also a noun, modifier, and pronoun. I wouldn't be surprised to see it as a verb.
'anpa' means "bottom" or "down" as noun or adverb. "lower" or "go down" as a verb, apparently cannot be used alone as a preposition, despite temptations that way
'ante' - "different", "change" "otherwise"
'anu' is syncategorematic "or" I can imagine it as a noun or verb but haven't seen it.
'awen' I think this may be a modal, too.
'e' really is only functional, it marks the direct object of a transitive verb.
'en' is probably close to syncategorematic as "and" but it only joins nous and maybe modifiers, not predicates or objects.
'insa' is just like 'anpa' in most structural ways.
'jo' means "possess", "possessions," "character" and so on -- noun, verb, modifier, at least.
'kama' means "arrive" "become," serves as a tense marker for future, takes a predicate complement like 'ken' and 'wile,' "bring (about)", "event"
'ken' is a modal (takes a predicate complement) but also means "ability' 'permiossion" and thus "permitted," "rights" "legal" and so on,
''kepeken' means "uses" and then "useful" and, as a sort of preposition, "with (using)"
'kin' might be called functional (if 'a' were); it is a rhetorical flourish, emphasizing or adding to a cases: "iondded, too, moreover, similarly" and the like.
'la' more or less syncategorematic as a marker of conditionals, an adverb/context marker with non-sentences.
'lawa' is pretty much like 'anpa' again, but develops more fully in metaphorical uses.
'li' clearly functional -- starts a predicate (or ends a subject --a philosophical question).
'lon' is basically the preposition "at, on" which then develops a number of other meanings in context. it can always take its prepositional object as a complement, outside the usual rules of modification.
'mi' refers to the speaker and those for whom s/he speaks, so, "I, me we, us, mine, ours, my, our" Like some similar words it has a potential for development, but this has not been realized, so far.
'monsi' is just like 'anpa' and 'insa' applied to a different body part.
'ni' the one deictic pronoun/adjective -- overworked and confusing occasionally, forcing more careful formulations; pragmatic, but not syncategorematic or merely functional.
'o' functional, I suppose: marks vocatives, imperatives and optative/hortative and the like (directive use of language).
'ona' the only anaphoric pronoun -- not overworked so far, since its unclarity leads immediately to using repetition instead -- like all pronouns, it is hard to classify among semantic and pragmatic and paralinguistic roles.
'open' is probably a modal as well as the usual things.
'pana' is not too clear yet -- it does not seem to be a modal or a preposition, yet is it used to do the same sorts of things sometimes.
'pi' functional -- right grouping strings of mdoifiers within a left-grouped structure. Though it has been used as a verb for "owns."
'pini' may be a modal, like 'open' and 'awen'
'poka' means 'side" and is like 'anpa' and 'monsi' and 'insa' etc. but it also has a separate use as a preposition meanin "with (accompanying)"
''pu' seme li sona I don't treally think it means "uncarved block" but I haven't seen anything else about it.
'seme' marks a fill-the-gap question (Hw question in English)so it has at least pragmatic and paralinguistic significance; grammatically howver it is totally normal.
'sin' content maybe, but note the curious meanings "new" and "again"
'sinpin' like 'monsi,' etc.
'sina' 2nd person pronoun, same status as 'mi' and 'ona' and 'ni'
'tan' the preposition "from" with developments like 'tawa' and 'lon'
'taso' restrictions, exceptions, contrary evidence -- partly syncategorematic, partly pragmatic
'tawa' the preposition "to, towards" with strange developments
'wile' just like 'ken'
I don't know if this clarifies anthing, but it givew you some more data to work with perhaps.
What is this all leading up to?