Here's the deal. You released this game in a closed BETA for testing. Good on you! we like betas, they help you work out bugs in your game. (that said, the bug report that I submit on a weekly basis for resolution resets has still yet to be addressed)
Here's the problem. Streamers have already had a go at your game and have moved on. So you have lost that avenue for advertising. You have your own launcher and don't use traditional store platforms because you didn't want to pay the Steam Mafia tax so now you're in a predicament. Not many know about this game. Result, small player base and long queue times. We can only do so much to help!
You need advertising and or partnership with a company that has a community base that accesses their store. I.E. Steam. Have you considered this?