Ah! Well as a level 4 Referee, an hour is probably sufficient, I tended to go for 1hr 15.
But the commitment and time elements are more around level 4 assistant refereeing. Clubs are generally more engaging and hospitable.
There is probably a bit of hanging around, chatting and what have you but the expectation is that you are there. I like to get a drink with my team, start to get to know you if I don't already, catch up with we do. Early pitch inspection to make sure no issues there. Remember, crowds are significantly higher and spectators are generally there earlier so there is a greater admin if the game can't go ahead the later you call it.
Team sheet exchange is more professional, as in you actually have a tike to do it and on some step 3/4 leagues involves manager and captains.
My day generally looks like
90 mins before - arrival, find out where going, intros etc.
75 mins before, brew and a chat, prematch instructions.
60 mins before get changed into warm up gear etc.
45 mins before team sheets - post team sheet admin
30 mins before warm up
10 mins before final checks
5 mins bell rings
And whilst all of these things can be done, I don't want people feeling rushed and stressed by zipping from one thing to the next, a nice relaxed approach to the game is what I am looking for. And there's ways that one person whom wants to monopolise your time chatting.