Erica,
There are only two stream crossings that were risky in any way shape or form, and they were not too challenging at all. I was also hiking alone, so I acted in an abundance of caution. The only tricky/intimidating part of these two crossings is that there are small waterfalls immediately after where you are crossing, so if you were to fall you'd tumble down those. Otherwise, they are a piece of cake. You'll see in the pictures.
The first is the Morrison Creek crossing, which happens on the descent into the canyon from White Wolf:

So, it actually looks pretty wimpy from this picture, but it was my first stream crossing in a while and I didn't want it to be my last. I looked slightly upstream and found a better option: a log that crossed the creek…


It wasn't the appeal of keeping my feet wet (my feet were wet for 50% of the trip, probably), but it seemed like a safer option all around. My reasoning was that if I were to slip and fall on the "regular" crossing, I was going immediately overboard. If I slipped and fell on the log crossing, I would have time to recover. I also was able to gently toss my pack across the creek so that that wouldn't burden me if I slipped. It was maybe two or three steps on this log (it's not very wide, but it's stable) to cross. No problem.
The second creek crossing is the Register Creek crossing that is roughly 6 to 8 miles past the Pate Valley junction:

This isn't quite as clear of a photo, but it's the best one I have. This one was a little deeper–I'm 6 feet tall and it came up to maybe mid thigh–so 2-2.5ft. It wasn't too bad at all, but earlier I grabbed a nice sturdy hiking staff along the trail to help me balanced. There's a part that looks like a small stone path, and that's where you want to cross. There is also sort of a small "shelf" of rocks to the right of you as you're walking, so that helps a little. It was cold, but not difficult.
I suspect that these crossings will be even easier by the time you all are hiking it, since I did this part on May 17th.
Also, I just realized you can tell how pedantic I am by these posts…