To have a starting Age option is really nice, however, it would be even better to also have an ending Age option, that would determine the maximum Age players can advance to.
This is doable in scenarios btw.
I saw the Ending Age text within the strings.txt file, so I decided to make a proper request here. Appears to be a missing/pending feature IMO. It would be great if it was eventually added in custom games, that’s all.