Since the round trip isnt 150 miles or something, imo the main concern would be getting the charging in during your super off peak time. The "complete charging right before departure" advice is more around the fact that, with a cabin pre conditioned and battery warmed, you will usually use less battery in the beginning of your trip making those things happen.
Its not like you are not using that electricity at all, it is just "switched" to doing that stuff from the wall connector vs the battery of your car when you are on the road at the beginning of the trip. In your case, for your regular commute, it doesnt matter, so its likely "easier" to just have charging set to begin shortly after your super off peak period begins.
This would be helpful as you settle into your normal routine of just plugging in when you get home, and let the car start charting in the middle of the night when your electricity is cheap, without worrying about if it will be done on time if you did a lot more driving than normal.
Trying to time it to be done for your normal commute means that, if you did a lot of extra driving or something, you might not have a full charge the next day.
On the "charge every day or every other day" thing, there isnt any reason not to plug in every night, if you have charging in your garage. You dont "have" to, of course, but there is NO reason not to. Tesla specifically says there is no advantage at all of "running it down to charge it back up" so there isnt any reason not to charge every day unless you just "dont want to" for some reason.