The comment element text size is less than the normal element label text size and it is very hard to read if the zoom of the action flow editor is set to anything less than the default (and I work with it zoomed out to allow me to see more of the action flow at one time).

e.g. see below how the message element title is bigger and easier to read than the text of the comment which is quite tricky to make out.

My suggestion is to either make the comment text size bigger, or to allow this to be a preference in Service Studio.