Indicators?

Yes these would be nice features. I definitely try to never leave mine cocked. If I’m hunting and don’t get the shot I just fire the shot eventually in a safe direction. However, I definitely have found myself unsure and pointing the gun in a safe direction and pulling the trigger to see if it is cocked. As far as double feeding I’m a forgetful dope and have never done it (knock on wood). I’m my opinion it’s super easy to avoid.
 
While a cocking indicator is a nice feature to have, I personally don't trust them and double check for myself when I'm in doubt. Treating your airguns as firearms goes a long way in regards to safety. Although, some airguns are different. There's no way to extract a pellet/slug unless you shoot it in a safe direction or push it out with a rod. I do like having an anti double load feature but I always find myself checking a second time and knowing what condition my airgun is in.