Hi JerryJason,
I’m unsure why you are seeing such slow speeds. We don’t cap download speeds in any way.
If you want to troubleshoot the Launcher issue, make sure to try these troubleshooting steps then follow the instructions towards the bottom and post your Debug Logs.
If you want to try the Source version. You will be downloading files from Github, so it bypasses the Launcher entirely. You will likely see the same download speeds that you see downloading from any other website.