You sir have answered your own questions.
This will be the only chance they have to get pictures & data that close to the rings plus arcing through that gap provides the proper angle to achieve the orbit. There will be more data on the rings in it's 4 yr, mission but that flyby is the closest.
The next big event:
Dec. 25, 2004: 02:00 UTC Huygens probe separates from the Cassini orbiter and begins its 21 day journey to Titan. Dec. 25 counts as day one and Jan. 14 is day 21.
Jan. 14, 2005: Huygens begins its descent through Titan's cloudy atmosphere, where it lands on the surface about two and half hours later. The probe is scheduled to encounter the upper fringes of Titan's atmosphere at 09:00 UTC.
Other highlights of the Saturn Tour include close encounters with Saturn's moons Enceladus, Titan, Hyperion, Dione, Rhea and Iapetus.
Awesome success that has been made with the The Little Rover's that could on Mars (Spirit & Opportunity) that still provide excellent data & pictures on there extended mission & now Cassini, that will open new doors on the mysteries of Saturn, it's Rings & her Moons.
Not to mention that the door has also been opened by Burt Rutan/Paul Allen with SpaceShipOne, the first private manned mission to space piloted by Mike Melvill, the first civilian to receive astronaut wings!