I think adding a user style change settings in nodebb would be a good option. Especially that other forum engines like discourse have this feature for a long time.
Lavender Theme, topic name some where in replies.
One of the things I like of this theme is the last replies in the category nodes, unfortunately, it's confusing to me sometimes as I dont know what topic the reply is even for. Perhaps a title where the posters name is currently? Then you could easily add "User posted" instead of just posted at the bottom? Perhaps configurable, or would we need to spin off a new theme for this to work? If the latter, might give me something to work on.
Maybe the design can change to:
psychobunny <link>posted 6 days ago</link> <topic text paragraph goes here> in <link>topic name</link>