For us the most important thing is to collect eggs. Ii's all too easy for them to get broken in the nest box and the next stage is an egg eating habit that is very difficult to stop. Setting aside the rat issues and the rare occasions of hens dying, it could be possible with a secure enclosure to double up on feeders and drinkers, leave the pop-hole open and leave chickens for a few days. But broken eggs would be almost certain and that could be a disaster.
To stop rats, mice and worst of all slugs getting to the feeder we put a weighted bucket over the top.