Arches deserves a full day of hiking, in my opinion. Start early morning at the primitive loop, where you will find lots of arches, plus the Dark Angel rock formation. This loop can easily be done in half a day, giving you the afternoon to visit the other rock formations. I highly recommend visiting Delicate Rock before its invaded by tourists, maybe just before going to the Primitive Loop. Please find all ways that you can walk around the arch, it will give you beautiful perspectives. Balance Rock is perfect when the sun is coming down, see below.
The Primitive Loop area. I am going out from memory since I haven't created a map for it yet. Most of the arches in the first half of the trail are side trips from the main trail, with the exception of the one on the left (below). It is incredible how fragile it is. You will notice that the viewpoint is not close to the arch, because ................ see those rocks under the arch ? Yes, it is falling apart and you don't want to be under it when that happens. If I remember correctly, you will keep taking short side trips to other arches, like the one below to the right.
You can do lots of tricks with the background of the arches in here. Unfortunately, at this time I didn't have a good eye and those pics dont' do justice
Ok, Dark Angel is the last structure at the "top" of the loop. At this point, I think most people just turn around. You can complete the loop, but there is no more trail at this point.
You are going to start hiking on slickrock and follow rock cairns in order to see where the trail takes you.
It is fun because you pretend to explore an area that doesn't have a trail and because few people do it. There are no arches in this area, the fun is to hike it.
These were taken from the Balanced Rock area. The beautiful La Sal mountains in the background. I think that late in the afternoon is the best time to photograph this area since the sun will start setting and highlighting the red color in the rocks.
On a separate occasion I took a quick visit in Winter (Thanksgiving) to the park and the snow really makes it so beautiful: