At this point there should just be a group chat you can join and once you're in it, you can just type to the people you want your texts to be seen from. I've mentioned a similar suggestion before, but I doubt it will get added anytime soon.
If there is a group whisper instead of car whisper and general whisper, it would be better. imagine having to type /cw /w or whatever the command is.
If it was a joined chat similar to setting your chat filter, and just typing in chat, i think it's more convinent that way tbh.
+1