Yes. See Snowflake abuse - #3 by WofWca.
But I’d probably work on automatic updates. AFAIK vulnerabilities in Snowflake proxies have never been discovered, but just in case.
Yes, after Snowflake they use Tor the standard way. Snowflake is just about censorship circumvention and so much about privacy.
Judging by the fact that you do get Snowflake clients, there is no need to do anything else.
Probably not “critical”, but you never know.