When one uploads an image/screenshot onto the forum, I see that it gets resized into a square. This might cut out the image. What I'd like to suggest is that if an image's size is too big, the image would be resized smaller, along with an option to view the original size of the image
My second suggestion is to implement a direct messaging system, like on other forums. Pretty much self-explanatory, and it especially can come in handy to avoid the discussion becoming off-topic.
Lastly, an admin might want to disable normal users posting a discussion into or adding the tags "Accepted Suggestions" and "Denied Suggestions".