It would help to know what kind of activity you are wanting to use this for. For instance, if it is an online text writing assignment, you can create your own "stoplight" stamps for use with annotate PDF's. They would need to be added by an admin.
Other activities it may be able to create a "stamp" for use with Generico filter, PoodLL Widgets, Snippets for Atto, etc. In other words, just add a picture in the grading feedback.
There are a LOT of special characters that can also be used to make a scale. For instance, I used to use this as a scale for some activities: ☆☆☆☆☆, ★☆☆☆☆, ★★☆☆☆, ★★★☆☆, ★★★★☆, ★★★★★