The current aggressive icon and the upcoming enemy level display are only one part of the current stage of edits.
To me this is the most important thing to keep in mind, no matter where they go with the system in the coming months. Until they declare "This is it, we are finished with serious changes" then everything we get will be part of Something Bigger. I don't mind the aggro icon at all, but I do look forward to being able to see the level, even if just so I know what can be easier avoided as a Botanist (Is it many levels above me, or only a couple for example) as well as the challenge of individual mobs in a group (Green coloured group, but individual beasts can kill people in single hits at times currently!)