True, your English is fine. Not perfect, but even most native English speakers don't write perfectly. And many of them write pretty badly!!!
And even if you feel that English as your second language is a weakness or a hindrance, you can use that feeling to motivate yourself to improve your English proficiency.
You're lucky that you have this great Steemit platform on which you can publish your English for a global audience ... and a potentially massive audience. On this platform, there are many posts written in sub-par English, and I know that you do not want to group your posts with them.
With your interesting topics, your clear perspectives, and your good-quality writing, your posts are among the better ones on Steemit. Keep it up, and keep improving!!