Nice, by boat was probably really cool! I heard the waiting list is years long now to get a rafting permit.
We did walk the North Kaibab trail a few years ago, down to the river and back up the same way. Very nice too! Doable in two days with no problem, but we took our time and enjoyed it for 3 days.
Your plan sounds great. Probably better than catching a shuttle back to North Rim, it's a long ride.
My dream hike is actually a rim-to-rim-to-rim. Not sure from which side, probably North. Also doable in 2 long and difficult days, but I'm thinking 4 easy days, including 2 nights at the bottom. I really hope I can set it up before I'm too old !lolz
Have a great week end, !ALIVE