over time will payed for characters become free, for example when new ones come out, or could they be made free but have payed for skins or have the collars be gated behind patreon instead of the characters?

As much as I would love for them to be, I honestly don't see that happening, but it could happen.

Heya all - sorry for the slow response. 

I think with a new addition of a playable race we'll bump the t'chan into a free feature. I wasn't the one that won the patreon poll this time though, sadly