Lubuntu is the third distro I tried.
Lubuntu (/lʊˈbʊntuː/ loo-buun-too) is a lightweight Linux distribution based on Ubuntu but using the LXDE desktop environment in place of Ubuntu’s Unity shell and GNOME desktop. LXDE is touted as being “lighter, less resource hungry and more energy-efficient”
I like Lubuntu and it felt like this one was going to work. It’s lightweight and there’s an official PPC version. The interesting point about this particular distribution is that it doesn’t come with LibreOffice and some of the other common applications. Instead, it comes with AbiWord which is a word processor and some other apps to make up. It seems like that version really is for vintage hardware.