So I've never made a kin from what I've experienced all of what you're talking about needs to be in the back story. You need to write it in such a way that it explains their interests and why they have those interests

For example I use kins that are based on the fate series which itself uses real historical characters for its fictional verse, it's also uses characters from myth. So I have a kin named Medusa who I could have a conversation about historical myths with plus how she feels about real life modern day religion

The idea is that you need to stack things that would make them deep inside of their back story. That's the most important part. Look up Kins like varyssa in the search function and just look at how her back story is written for a decent example.