Again you have the right idea.
On our last visit of the museum, we had started out following Rick Steves's doodling - but indeed effective - map all the way to the Sistine Chapel. It would be wholy qualified as a zoo, as Pauline would put it. As with every mass tourism site, especially mass tourism sites in Rome, we could not wait to get the hell out.
Then we saw thisbiblical exodus out a side-door, the Rick Steves's side-door.
As huge crowds from 5 continents, herded by screaming guides, are squeezing out of this tiny door, we decided to go where - wherever - they were not going. We continued the long route (about 20 minites), going from one treasure-filled deserted room to another. It was truly splendid isolation. In some of those rooms we were the only people there. Of all the times we have visited the Vatican museum, perhaps 4 times, perhaps more, that was the visit we enjoyed most.
Maybe I should make a Rick Steves alternative map, showing all the places he tells you to skip.
I am not a Rick Steves hater. I already said I liked his maps.
For some things.
One big problem is that he has established a world map for … the world ! Everyone from every country follows his map, which creates its own Ricks human traffic jam. Moreover, what RS tells you to skip is based on his own dislikes. One example is the Santa Cecilia church in Trastevere. He said the basement has nothing special. Actually it has an extensive and excellently preserved site of excavation ! It was one of the highlights of our last trip.
Conclusion: yes, after the Sistine Chapel, just continue straight and take the 20-minute walk out of the museum instead of the RS side-door short-cut. You will have a totally different experience, all by yourselves.