Yes, they can spice things up, as long as it isn't a constant stream of complaining... otherwise... Blurt. :D
The length of post is an interesting one, as I find that my longer ones (not too long) get read more. Though, very few of mine are under 1000 words. The longer posts also might not get as many readers, but the comments are far better quality. Short posts rarely instigate high -quality discussion.
Experimenting through content is all part of the fun.
I agree. I have yet to even look at Blurt but I think you've saved me the effort.
Something to experiment with for sure.