As you yourself noted, you were not aware Ruby 2.2 is a big performance regression. Nor did you know about the patches we use for Ruby 2.0. This is all fine, but you’re forking the install, and you will never know as much about Discourse performance as we on the Discourse team do.
Which is why people should stay on the Docker install, which always automatically reflects optimal Discourse settings, unless someone is basically holding a and forcing them not to use Docker.
You also lose the one-click web updater, of course.
edit: I don’t mean to sound negative, because I appreciate your hard work, but there is a reason we ask everyone to use the Docker based install, and it’s the only one we can support.