A common system in open world games now is some form of alchemy - collecting plants in the open world and turning them into potions or food or whatever. I LOVE picking up the plants. I love being able to recognize them and know before I pick it up what's it's for, or when it's something new.
These systems always fall down after that. The sheer number of plants mean inventory management nightmare, which I hate. Maybe you have a few recipes you know to be good, like Baulder's Gate 3's speed potion, and you just sort of let the game automatically make the other things. In Dragon's Dogma 2 most ingredients combine to a few things - any 2 ripe fruits can be made into dried fruit which can be combined with a number of leaves into a great healing item. Breath of the Wild's cooking system did a great job with utility and fun - eating a million cooked meats during a boss fight but also discovering candied apples. Ultimately they just end in too much inventory management for me.
Proposition
A 'little guy' version of Strange Horticulture (a game I consider to be the perfect Small Game).
You go into the forest to collect plants. You have a drawing of some kind and maybe a description to recognize the plants but when you look at them in 'real life' they may not be exactly the same so you have to do some reasoning.
The reference material is of varying quality. The plant may be in a different stage of life than the drawing. You may disagree with the name of the colour used. Part of the game is collecting the references, part is collecting the plants. This slows it down a bit so it's not just inventory management.
Plants that are common and useful will become familiar, punctuated by exciting searches for rare plants.
Maybe you can make a small garden so you have the most useful near you, but it requires the most care.
I'm growing some plants on my balcony. I set them up and threw in seeds for sweat pea and chives. I know more or less what the final plants look like but the seedlings are mostly new to me, especially when some other random seedlings came up.
The drawing below was from 2 days before the picture was taken. Is it still recognizable as that plant? Easily if you've seen it before and know what the final leaves will look like, maybe not so easy if you're completely unfamiliar.
May 30 (13 days since planting)