My biggest side project is about grammatical gender in French, published as a research project on wikiversity[1].

It did made me go through many topics, like dual, exclusive/inclusive group person.

Still in a corner of my head, there is the idea to introduce some more pronouns to handle more subtilty about which first person we are expressing about[2]. The ego is not the present attention, nor they are that thing intertwined with the rest of the world without which nothing exists.

[1] https://fr.wikiversity.org/wiki/Recherche:Sur_l%E2%80%99exte...

[2] The project does provide an homogenized extended set of pronouns with 6 more than the two regular ones found in any primary school book. And completing all cases for all nouns is the biggest chunk that need to be completed, though it’s already done by now for the most frequent paradigms.