Thanks a lot for the response. It seems like a dealbreaker that calls and camera don’t work on it.
I haven’t used Librem 5 with NixOS, but was considering it. Hence I asked.
Btw, there was a discussion about extending ZRam, which seems to greatly improve responsiveness and performance: Why and how to extend ZRAM on L5. A revolution for Librem 5 stability! - #65 by shak
Maybe you can try that?