I think most conventions in our society are good. It is forbidden to attack or murder somebody unless you are defending yourself is one of the things that is just common sense for most human societies. Knowledge is build upon conventions, in specific the conventions we have in science. I would agree that the scientific community achieved a lot in the past 300-3000 years so they seem to have some decent fundamentals/conventions, that said they sure are not flawless.
In other parts of society our conventions seem mostly decent as well. I do think most parts of the law, at least the part normal citizens encounter seems fair. Even tho police might be corrupt I think most of the laws themselves are just.
With all that being sad I do not think that you should shy away from changing something just because it is fundamental, but you should respect that it is A. very hard to change and B. might have far reaching consequences that are tough to predict.