I think there should be a /rank command. It could replace the /playtime command.
Here's the things I think it should do:
Show your playtime.
Show your rank.
Show how long it's gonna take and what the other ranks are.
Just something that seems helpful to have.
This is something that I would have to create myself or have someone do it for me. I might look at modifying what we already have as most plugins are open source.