Thanks for the feedback!
You should be able to sit on the sofa (or even the chair) in the Apartment to recover your sleep. Though this recovery is slow and Sleep consumables are encouraged!
I should probably make the Hunger and Sleep slower I guess
And the screen should not remain grey when you die, I tested it several times and it was working fine, hopefully it's a rare bug
There's also a Hypersleep Chamber which can be unlocked as you upgrade your Apartment