Hacking to make a different default than “Godfather” would be easier (but not very useful) than adding a Custom Type selector. But a dropdown WOULD be nice. Associations use the Person Reference Editor. And it is pretty basic. Nick recently committed an improvement to the 5.2 master that will at least enable drag’n’drop for selecting the target person.
But there is so much more that could be done with this alternative form of relationship. Here is dialog mockup (no code, just photoshopped) that would encompass a variety of outstanding requests for the editing of Associations:
PS: You might want to consider consolidating your “Godfather”/“Godmother” into “Godparent” and “Godson”/“Goddaughter” into “Godchild”. The Gender is already a Filter option. So you still have the same granularity.
A discussion exists for hacking Gramps Keybindings… although it is focused on disabling certain hotkey combinations, not adding new ones.
The discussion is linked from the “See Also” section of the Keybindings wiki article. It has been re-opened if you want to expand the scope of that discussion.
You might want to consider downloading and installing the experimental CardView addon collection by @cdhorn.
The current incarnation adds 2 new view modes in a new Tag navigator category.
I also find not being able to clipboard a fully formatted Name or Place to be inconvenient.
As a workaround, add the “Quick View” gramplet to the bottombar of the View and set it to the “add-on “Biography”” quickview in the Person category. You CAN copy to the OS Clipboard from that area. (Albeit with the context pop-up menu “Copy” command instead of the highjacked Ctrl-C.)