If a subreddit is about a visual creative medium, then the image posts won't be lazy, as they will tend to be people's Original Content; and they will frequently spawn good discussions on how to achieve the effects shown. See:
And of course, there's the great and under-explored genre of "hobby X but for old people who aren't interested in the fads of hobby X" subreddits, e.g.
The few times I've looked at the comments sections it's been pretty good. But then, I don't visit the subreddit (or any subreddit); I just join it and then wait for things from it to show up on my front page. So I only see posts from it when those posts get wildly popular, or at least more popular than posts on such a sub usually get.