However, in the end you'll end up wanting to express much more and the language is just not able to do that, you'll end up lost in the compounds, and things become unclear pretty quickly.
Yip, there are definitely topics I butt into where I hit a wall too -_- . But with time I got much better at navigating them and have had several-hour-long conversations IRL as well as online using just Toki Pona (without resorting to compounds really - I don't know if it's what you're referring to, but compound phrases with fixed meaning aren't really in the spirit of the language). There are people online who I talk with regularly exclusively using Toki Pona.
Another practical step could be to identify a specific minimal set of language units required for any given popular nonconstructed language. Is this already a thing?
You mean something like this question?
This seems to be reaching for exoticism for the sake of exoticism, given that the standard term is the metaphorically identical "spaceship".
It can't even be justified by the restriction to "the 3000 most common words", since ship is #1208 in COCA.
Talking about daily life works pretty well (general chit chat - asking people how they’re feeling, what they’ve been doing, assuming you know something about their lives already there won’t be many ambiguities). online, I often share pictures as I go (they give points of reference). So I can say “mi pali e pan suwi” (i made sweet bread) and show a picture of a cake; my friend could say “ni li pona ala pona?” (is it good or not?) and I could reply appropriately. I could say if I plan to make it again, maybe talk about the ingredient composition slightly.
Commonly also, sharing toki pona memes/making jokes, finding deliberately silly ways to refer to things. (A running game I have with a friend is referring to lots of places as “tomo awen” (waiting house). Hospital? “tomo awen”, because most of your time there is waiting. Waiting in line at a supermarket? “tomo awen”. And right now, our homes are also “tomo awen”, because we can’t go out...).
One thing I’m looking forward to doing when it gets warm/we’re not quarantined anymore, is going to the zoo, walking around, and deciding how to describe all the different animals “soweli pi lawa sewi” (animal with a high head) for giraffe for instance. Going to a gallery or the like would also probably work pretty well - you can point at things, talk about how you feel about them. (It would be more about immediate experience than prior knowledge I guess). Any activity/situation with a lot of ready-to-hand context is likely to work.
Doing activities where you have a fixed frame of reference a language with limited vocabulary can work quite well. I played 2-player local coop of Wilmot’s Warehouse ( https://www.youtube.com/watch?v=TAcyPIJYOx4 ), where the sould of the game is categorising packages with various random/abstract designs and deciding where to put them in a warehouse. That would probably be a good exercise for any language, but it worked in toki pona.
I met up with someone I didn’t otherwise know and we talked about our professions, where we grew up, etc. (One cheat is that in Toki Pona’s 120 word count, borrowed words aren’t included - but there are conventions for transliterating words from other languages if you want to talk about English (Inli) or America (Mewika)).
You can go shopping and cook with someone - trying to describe what ingredients you’re looking for is I guess a game, and once you have them at home you can probably issue instructions with enough accuracy using Toki Pona’s vocabulary.
What’s difficult to talk about? Time and scheduling, especially under time pressure. Trying to clear up a scheduling confusion via txt messages with a friend was absolutely zero fun, especially when misunderstandings start creeping in that can’t be quickly rectified. Scheduling discussions have been the ones where I’ve hated Toki Pona the most.
Talking about technical matters doesn’t work - I can’t talk meaningful about maths in toki pona beyond the absolute vaguest of euphemisms - and while people have tried to state theorems/etc., it basically doesn’t work in my experience.
Talking without a concrete frame of reference can be hard. If I can’t see you, can’t share pictures with you, can’t use emoji, etc., the range of what I can communicate is severely limited. I can say I worked, I can say I’m feeling good, I can say what country I live in. I can talk about eating flat round bread with red paste on top (pizza), and that my girldfriend didn’t like it or whatever...which is still manageable chitchit I guess, but much more limited. (There are toki pona songs that work well at this level of speech though - e.g. https://www.youtube.com/watch?v=Bjlwov4JiD0 ).
mi wile e ni: tenpo lili la mi mute ale li ken tawa tan tomo awen pi mi mute!
https://www.reddit.com/r/mi_lon/comments/fpjomk/soweli_pi_la...
The best place to learn is from the official Toki Pona book by Sonja herself:
If that's too much of an investment, the next best thing is the course "o kama sona e toki pona" by jan Pije:
http://tokipona.net/tp/janpije/okamasona.php
There are active discords, subreddits, telegram chats, facebook groups, etc. - probably the handiest list is in the sidebar of /r/tokipona:
https://www.reddit.com/r/tokipona/
There are a bunch of different communities/resources - I learned a lot from the "ma pona pi toki pona" discord, which is probably the best community for learning Toki Pona (people are generally friendly and generous with sharing knowledge). There's also a lot of music written in Toki Pona on youtube https://www.youtube.com/playlist?list=PL2eg_FknCSeoWL6tFBKOn... (some of them are decent!), which is nice for passive consumption.
And, as I mentioned elsewhere the meme reddit mi_lon https://www.reddit.com/r/mi_lon/ is pretty good as well.