It's tough, I know. You really need to focus on quality before quantity.
Don't worry about old flags, as long as you produce unique content that will be much more important.
Browse the trending categories and exclude all bot inflated posts, then look for patterns that you can easily copy and use in your own post.
All the best!
I have thought of that, most of the trending topics are things I have no expertise in like Bitcoin. I have even tried posting some funny memes and those go unnoticed. I joined Steemit due to unemployment so I can have a little money. I was making more when I first joined. Then the people who had enough SP to upvote me vanished.