Last I checked, Signal still hasn't fixed their giant UX problem, which is that when you first install the app, it announces you to other Signal users on your contact list. This makes it completely unusable for anybody who actually needs, you know, a secure messenger (like a domestic abuse victim).
I mean I use Signal every day and I love it. But it irks me that they're like "Oh we're super secure. Unless you're trying to get help from your abusive husband, in which case, guess what, we just snitched on you to your abusive husband! Good luck with that!"
I used to run a TFTP server on my router that held the decryption keys. As soon as a machine got far enough in the boot sequence to get network access, it would pull the decryption keys from the router. That way a thief would have to steal the router along with the computer, and have the router running when booting up the computer. It works wirelessly, too!