I'm think about a week or so hike in AZ in September or October, so I'm looking at your list with interest.
Ron has pretty good information regarding the water resistance of Momentum fabric here. It sounds like with umbrellas, and assuming you aren't expecting prolonged rain, you might be able to get away with no rain jacket. However, since it is your only insulating layer, and down becomes useless when wet, it would be a risk. Depends on how cold you are expecting it to get. If you are bringing a down jacket, I assume it will get cold enough to use it.
If you could provide expected high/low temps and precip expectations for those of us not familiar with AZ weather in March, it would help evaluation.
As far as posting format, if you have a gmail account, then google docs is a nice way to publicly share a spreadsheet. You can publish is as a web page and then share the link like this.