Yes, you've definitely improved your schedule. 2gypsies hit it on the head when they point out that you can do both Canyonlands and Arches from the same Moab area CG. But I'd still give myself the 2nd through the 6th as you have planned. Besides the two parks, there is a lot of other places to see, such as the roads along the river above and below the highway. Or take the LaSal Mountain Loop. It goes up into the mountains above Moab and there an excellent view of much of the Canyonlands area from up there. Plus, it's much cooler in the middle of the day. If you get daring, you can even rent a jeep in Moab and try some of the tamer trails. Maybe visit the Island in the Sky one day and do the White Rim Trail the next. You'll be down on the road you saw from the top the day before. It's a good way to really get right there in the scenery.
BTW, the only reason to spend even one, let alone two nights in Page is if you're planning some sort of water adventure. Otherwise, Page gets very hot by that time of year and there's precious little shade.
