It's important for travelers to know when restaurants, attractions, etc., are open. Writing hours is complicated: does it close at 22:00 or at 10:00 p.m. or at 10:00PM or at 10:00p? What about different hours on different days of the week or at different times of year?
Provide a GUI tool that allows users to specify all of these details, perhaps using a pop-up menu pre-filled with times of day, and allowing different times to be set for different days of the week. When the GUI is closed, it returns the user to the regular listing, with the correctly formatted times pre-filled as plain (editable) text.
This won't cover everything (how do you set a closing time of "Sunset"?), but it would help standardize and simplify the times for >90% of listings.
It's possible that this could be done in conjunction with the work on T48225.