So you are ready to graduate from the Corridor Trails. Learn the Canyon and look at the Threshold trails next. For dayhikes, the Hermit Trail would be the next logical progression. It can be a Rim-river-rim dayhike if you are really fit. It has views like South Kaibab except to the west not the east. Anyone with a Backcountry Pass from Hermits TH gets the code to the gate. But I thought they changed the code monthly. The gate is open from Nov 1(?) to March 31(?). The next progression from a Hermit Rim River Rim would be a Hermit-Boucher Loop. No River, but you don't need to go to the River to enjoy the Canyon. There are a lot of other great things to discover. And some great climbs (Battleship). Grandview is a nice threshold trail. The hike to Horseshoe Mesa and the caves is a nice dayhike.
Look at these two bookshttp://hikearizona.com/books.php?REV=1&ID=60&STu=http://hikearizona.com/books.php?REV=1&ID=24&STu=
They will fit with your progress.
Spend the money and buy this maphttp://hikearizona.com/books.php?REV=1&ID=928&STu=
It has all of the Use Areas and maps.
Eventually you will progress to overnight trips and some light backpacking. New Hance-Escalante-Beamer is on my list. I want to see the LCR. I also want to get to Royal Arch. Then you get George Steck's book and Harvey's notebooks.
You will (must) learn tricks on water management and cacheing. And then there's the North Rim! The North Rim is a world unto itself. Very different from the South Rim. More water. Ancestral Puebloan ruins. Wotan's Throne was Harvey's favorite. The ashes of Harvey and Roma (his wife) were scattered up there.
Have fun. Enjoy. Develop your skills, Know your strengths and your limits.
ONCE MORE INTO THE BREACH, DEAR FRIENDS, ONCE MORE!