I think there should be a kind of client mod that cooperates with Carpet.
E.g.
Reading the pos info from loggers such as projectile logger; render a box at the place so that it would be easier to understand;
Render a chunk loading map from the packets sent by Carpet Server;
.......

While it might be realized in other mods, I still want it to be Carpet Client. Also, the real carpet client hasn't been officially released XD.

P.S. I hope it would be like: "WorldEdit and WorldEditCUI"

yes, its being worked on, but not a priority for anybody it seems so its left as is.

For the time being I am planning to bring some client-synch options and a few custom packets to control UI and in-world client elements from the server via scarpet

hmm...
I'm planning to make a mod which fulfils the feathers I mentioned above, about rendering specific boxes or shadows according to logger/command feedbacks, just like [x:xxx,y:xxx, z:xxx] working in VoxelMap.
So I wonder if there is some fixed format for info such as position, in CM, just as :
A position vec in logger is always printed in format "[type=Pos, x=100.0, y=100.0, z=100.0]"
Or some kindof better readable-and-recognizable message format?

@X-Green As to the world edit, I currently am working on a scarpet app which does it with relative high efficiency, if you want I'll send you the link to the repo

currently the only way to display client specific renders is via particles, which is fine, but gets super laggy. My plan was to utilize custom particle code that would send particle data to non-carpet clients and custom efficient render requests to carpet clients.

I think first steps towards it are done? Technically the internal requests for these can already be used - here with the overlay app.
Closing I guess.