Could requesting the bending of time be done daily to increase productivity on a long-term basis? Would this be safe to do?

This can be done on a daily basis and particularly if there is a high purpose. As is true for all prayer requests, any time a divine intervention is requested, there needs to be a high purpose to justify the intervention in the first place. This is subjective but can be determined through trial and error by an individual. It will always be safe to do because any increase in expenditure of energy will be factored into the time looping itself because it will carry energy with it and, if time is dilated, the energy will be dilated correspondingly. So the availability of energy will be extended proportional to the increased time available for useful work so people will not end up being exhausted in the process. Even though, by the clock, no extra time has elapsed, a significant body of useful work will be evident in the output results, but the individual will be no more tired than spending a corresponding length of time at such tasks as recorded by the ordinary clocks in the area.