Have you flown into Las Vegas before or been in this area before?
If not, some tips/things to keep in mind:
1) Mccarran international airport utilizes a single location off airport car hire (car rental) facility. About 10 minutes by bus. When you finally make it down to the lobby, look for the signs. However, keep this in mind when you return your car so you have enough time to get back.
2) McCarran to the North Rim Lodge is about 4.5 hours (I-15 North, then into St. George/Hurricane, to Fredonia, AZ, down to Jacob Lake AZ, then down to the lodge). Since you'll be passing Jacob Lake, definitely stop in here - they have a nice lunch counter and serve pretty amazing home-baked cookies. A nice break before you do the road down to the N. Rim proper. I'd also strongly consider stopping for supplies (either at the gas station right before you get on "the strip" close to where you exit the rental car facility, or up the road 45 minutes in Mesquite, NV. You do not want to get stranded in the American Southwest in the summer without a LOT of water and some general food supplies.
3) For any sunrise or sunset driving in the North Rim area, be very, very aware of animals, particularly deer, which might be in the road. Don't speed here. The road to Point Imperial can be really narrow, be on the lookout for other vehicles.
4) Remember when leaving the North Rim that due to a landslide that closed Hwy 89 south of Page, you'll have to go the way you came in - back to Fredonia, up to Kanab, then east on hwy 89 to Page. Just under three hours the long way. I think you might go back an hour due to the various time zone strangeness between utah/arizona, can't remember offhand. Stop at the BLM station in Kanab - it's right near the Comfort Inn hotel, you'll drive right past it. They can offer any suggestions, provide maps, etc. Very nice folks.
5) Page / lower antelope: Get there at 8am if you can, there will be a line of cars at the gate. When the folks come to open, follow the cars down to the dirt lot. There will be a shack at the far left corner of the lot. Show your tripod and DSLR or MF camera and ask for the "photo pass" - 42 US dollars now (!! it went up) and you'll get two hours to wander around on your own.
6) Horseshoe Bend: be freakin' careful at the edge - no guardrails, 350 meters or so straight down, people die here every year from falling.
There is a lifetime of shooting to be done in this area, but I think your option 2 covers some really nice things. It still may be worth your while going through Zion on the way back to hwy 15, even if only to see the park and not shoot much. I guess it depends on when you need to back in Vegas that night.
-m