Lots of people find the Louvre overwhelming, because it is so large. I would say it is essential to go to this museum with a plan of what you want to see, and try not to let yourself be too distracted. You simply can't see everything.
I highly recommend, if you've purchased the Paris Museum Pass, going Wednesday or Friday night when the museum is open late, to see the Mona Lisa and a few other key things when the museum is not very busy. Then, call it a night and come back during the day to see any of the other things that interest you. In our case, we focused on their excellent Egyptian collection, and then headed to various places to see some of our favourite artists. We also made a special trip to the Babylonian section to see the Code of Hammurabi. It's not too difficult to navigate this museum with the map provided, so we were able to fit in a lot of things in a relatively short period of time.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC