I would also like learn from what other people have used as well so any input that others could give would be helpful.
* Redmine: https://www.redmine.org/
* Plugin: https://github.com/marius-balteanu/redmine_redcaser
My opinion: It's not worth it to try to stick all possible functionality into one tool. And the plugin architecture in general is horrible if the plugin is not maintained by the same group as the core since support will end quickly when the plugin maintainer goes away, or the core having too many breaking changes between major versions.
Advice: get a dedicated tool. Whether paid or self hosted it should be made specifically for test case management, and stay away from any tool that has a community plugin architecture