I did try going back to Settlers 2 last year and it was just as good as I remember it, it really holds up. At least the remake which is also the one I played when I was a kid.

https://www.gog.com/en/game/the_settlers_2_10th_anniversary

I'm gonna try Widelands from the recommendation of another commenter, it looks like it's a deeper open-source clone of Settlers 2.

https://www.widelands.org/

And The Colonists also looks great, a modern indie successor that also has the path network mechanic that I loved at its core.

https://store.steampowered.com/app/677340/The_Colonists/