Hiked over Ram Valley June 20th and rafted to about mile 4, when things started getting pretty narrow and wild and the sweepers started to get more abundant. Thanks for the input. It’s a great run and a great loop…as I rode my bike back up to retrieve my truck at Ram Valley trail head.
In a kayak quite a few times. There is some wood here and there, that while in play, can be negotiated in a kayak. Not sure that would be the case in a packraft. I’d attempt to give a play by play, but you’d have to know the run fairly well. Also, be aware and respectful of any private property signs around the falls so as not to endanger access to the creek for kayakers. This pretty much means you’re running the falls or trespassing. Don’t screw it up for those of us that run this on a very regular basis. Packrafters already have the upper hand on Ship creek given it’s a real challenge to get in there with a kayak given the military’s rules and penalties. Peters is the last local run (at least for me) that’s worth anything and it would suck to lose it. Sorry if this sounds a little defensive, but it’s a bit personal. 
On June 7th I hiked over to Peters Creek from Ram Valley and ran about 6 miles of Peters Creek down to approximately Mile 5. The creek was fun and fast Class II and III but got more wood-infested as I went along. Eventually the wood became too annoying and dangerous and I pulled out and hiked out the remainder. I suspect the water level is too low now, as I was there during the heat wave when there was lots of glacier and snowmelt.
Last fall (2008) I boated from about Mile 5 down to about Mile 2 and found the creek to be steady Class III, again with lots of annoying and dangerous wood (ie; sweepers and strainers). I took out before the section that is run by kayakers.