Just a suggestion:
Can splitting lobbies focus on NOT dividing players into skill categories, from what ive noticed this tends to kill lobbies, and instead split a room more balanced-wise by for example not putting all higher ranked people in a lobby, and all lower rank people in the other lobby.
Also this sometimes provides a miserable gameplay experience for people in the lower ranked lobby, as for lack of a better word a large percentile lobs around.
The higher ranked lobby firstly tends to live longer, and secondly provides a better experience imo, of course you could say theres some bias here because i often get thrown in the lower-skill lobpot.
Edit: Im not sure why i got downvoted, it was just a suggestion.