(Sorry for bad english)
Add a new badge for those users who are commenting on other users' submissions.
My brother wanted to give DA a try but got disappointed a few months later when none of this works got a single feedback. Back when I started I didn't get comments either but I continued on because I genuinely into art. But there are some who are just trying it out for the sake of boredom, others might just need to know that their hard work clarified(?) And some might just be plain narcissistic. Just one comment might help them spark that interest.
Of course there's a downside to this feature, most notably spam (would be great if users had the ability to block certain keywords from being commented but that's on another post) and comments that seem disingenuine. If you're just starting out I'm sure you'd be happy knowing someone recognized your work.
I think a way to counter this would be to make the owner of the artwork somehow approve their comment for the badge. Maybe make a small 👌 or 👍 icon on the corner of the comment post so when said user clicks it the user who made the comment will get either a badge that will increase in number and quality (like the llama badge)
Yeah, this feature might have a lot of holes and probably isn't the best but I want to know what you guys think.