Hi everybody.

(Sort of) first time poster here, though I've been lurking a long time.

I'm working on my first conlang. Not phonetics, though I know the dictum
about "phonetics first". Unfortunately, I'm not a linguist (I'm a computer
guy) and most phonetics here go way over my head, so in that regard I'll
stick with something simple and easy for Spaniards, as it matches my target
group (fellow roleplayers, mostly). I can always expand it later (I'll be
of course open to suggestions of any kind).

My conlang is not yet named, though I call it Gig for now, as the
conculture speakers are prototypical humanoid Giants.

So, I'm working on morphology, syntax, etc. Currently I'm thinking of a
VSO, fluid-S language, and I'm valiantly resisting the new-conlanger's
impulse of going down the highly-agglutinative route ;-)

The question I have is related to plurals.

So, in Gig, number is a variant of a singular/paucal/plural system. Let's
call these SG, PL1, PL2.

Singular (SG) is unmarked. PL1 and PL2 are marked with prefixes.

PL1 is sort of a paucal, but not used to count few things, but "definite"
numbers of things. PL2 is used when the number is neither known nor easily

So, for example: if you're talking about the passengers in a car, you'll
use PL1. If you're talking about the stars in the sky, or the drops of
water in the ocean, you'll use PL2. But you would also use PL1 if you're a
teacher and refer to the number of students in your current class, even if
they're 20 or 30 or more. Talking about your family would likely use PL1,
because it can grow or shrink, but usually does so slowly and, in a
specific point in time, it is a very easily determinable number (you could
always just enumerate all your family members, for example). Talking about
Spain's (or the world's) population would always be PL2, because there is
no way to determine the precise number in any way.

Choosing between PL1 and PL2 is really a subjective issue related to how
you perceive the number of items involved. If you're going to fly to Hawaii
and speak about the passengers that will be with you in the plane, you'll
use PL2, even if it is a specific number, because you don't know it and
can't easily determine it. The plane's captain would perhaps use PL1 if he
knows that the crew + passengers add up to 205 people. On the other hand,
if you are talking about a plane crash in the news (apologies for the
morbid example), you'll likely use PL1, even if you don't remember the
number of people involved, because it is a very definite number, fixed
forever and likely to be quoted literally in news reports and the like.

Of course, joke or ironic uses are possible, and perhaps even frequent.
Using PL1 to talk about a party (insinuating that it was a failure), or PL2
if you're having a romantic dinner with your partner and you can't get rid
of an unexpected newcomer (to clearly convey that "three is a multitude")
would fall into that pattern.

So, it's not really a singular / paucal / plural systems as much as
singular / definite / indefinite.

Are there natlangs that do this? How would you refer to these plurals? How
would you gloss them? And, more importantly: does it make sense, or it is
waaaaay too artificial?

Thanks in advance,