Even the smallest thing we do now has an effect on the general perception of the outside world towards Steem.
Our contributions are our own to choose. But it think its not just content that we can focus on. Our attitude towards the issue at hand is also important.
We are part of a society here and voicing our opinions is super important. Opinions voiced create a consensus on what we think this platform should look like. Flags are too aggressive imo and cheap in regards what your comment on a post that deals with issues in question can do.
Its more then ok to just create content but we are in a system that allows us to speak with our votes (for witness) even if we are scared to do so with our words.
Im still not sure if steemians vote witnesses at a high enough number.
To the question in the title: "Everything".
People need to realize that they have the power, even if they are the smallest of minnows, to have more impact on the platform then even the largest of whales. I wont share how i know this so you will have to trust me. :)
If you truly wanted to, you can find a way. Vague, i know. ;)