looks like a leafhopper to me - they will munch on the leaves a bit, but will be more of a pest of on other plants. If you see stippling, meaning all kinds of little round spots on leaves of plants, that can be the work of leafhoppers.

I thought it was a young katydid. Yes they will eat your plants.
When do the katydids start singing in your part of Michigan? In my part of NJ, we begin to hear them the last week of July. This has moved up, 6-8 yr ago it was the first week August.