"Give players X amount of time to make a decision on their turn in combat"
I don't mean to pick on this advice too much but, at least at our table, it is expected that most of the time when the initiative order comes around to your turn that you the player have been paying attention in order to have a course of action ready right away. Of course, there are times when there might be a few moments of deliberation, especially when something unexpected happened on the turn just before yours. We also should absolutely be patient with new players as they get a sense of how to play.
TLDR: Session time is precious. Pay attention, Know how your character works, Keep the action flowing with minimal delay