(Please pardon my writing length!) There is a 'best practices" issue I've been considering. I have been extensively editing some existing umbrella projects and also creating a few new projects, and realized that I didn't have a good idea of how the Related Projects field is intended to be used, or how it might best be used. Added to the mix is how to best combine Related Projects with Tags.
The root of the confusion is whether the best practice would be to (1) use a project's Related Projects field to only point toward higher hierarchy projects, (2) use the field to point only toward lower hierarchy projects, (3) use field to point only toward related by out-of-hierarchy projects, (4) some combination of those three. I feel that Tags are a better way to implement (3) in general when the relationship is loose, which leaves up vs. down hierarchy pointing.
It's in umbrella projects that using Related Projects for pointing down hierarchy is an obvious problem, because the list becomes so long that hardly any of it is displayed on the page (yes, you can display more if you notice the link to do so). So for an umbrella project, the more useful way to point to lower hierarchy projects is within the body of the project overview page, where you can use an outline format that's more informative than the Related Projects simple list.
So I conclude that the best practice for use of the Related Projects field is primarily for pointing to higher hierarchy projects, plus perhaps a small number of out-of-hierarchy but especially relevant related projects. Does this make sense (or not) for anyone else? Am I missing anything?
Examples I've been working with:
Jews of Belarus. https://www.geni.com/projects/Jews-of-Belarus/18585
Jewish Communities in Romania. https://www.geni.com/projects/Jewish-Communities-in-Romania/18148
Jewish Families of Turov and Zhitkovichi, Belarus. https://www.geni.com/projects/Jewish-Families-of-Turov-and-Zhitkovi...
Granadier Families of Belarus. https://www.geni.com/projects/Granadier-Families-of-Belarus/37781