Item 3 is the most important. Simply It's the hostel's job to make sure there are enough staff on duty at whatever time to cope with the typical load.
There is a major hostel in London where there was always a long queue for the reception desk -- to the extent that, if you just had a quick question, you had to try to push in front to ask it. This contributed to some reviewers' dissatisfaction with the hostel. A hostel needs to be aware when this happens, as it is easily curable.