Hi jietaka,
Yes, that is a good question. Given your last file, there was a lot to adjust in.
I assume three key parts for that answer:
• My impression is that each studio has even its very own standards.
• The use of a specific software might define the possibilities a lot, especially if the studio writes their own software.
• Last but certainly not least, I believe it is based on the character, the rigger, and the artists who create the base of any design.
The variables that these three contain will lead to a wide variety. My observation, in a nutshell, the elements are only provided as much as needed, to allow for the least amount of distraction and the best option to activate those.
Bret Bays, who works now since years as a rigger at Disney on many Oscar nominated or even awarded movies has a nice list of tutorials here on Cineversity. Example:
https://www.cineversity.com/vidplaylist/character_rigging_techniques_siggraph_2015_rewind/siggraph_2015_rewind_bret_bays_creating_a_character_rigging_pipeline
All in all, whatever you chose to integrate, will follow the idea mentioned already, not in the way and easily accessible.
I have seen many approaches in books, most of them are perhaps already outdated. But after all, those things should serve the artist, and whatever he or she needs.
All the best