Want to do this with my pup as well (no g/f though). My house mate's parents are on the GMC board and they've been feeding me trail condition info as it comes in.
Preliminary reports say the Long Trail did not suffer much damage, but reports were still coming in, most of the damage is to side trails and the roads going in. I'm sure more info will be had over the next few weeks.
Anyway, my thoughts on your list...
Do you need a wind shirt AND the rain jacket? is there a reason to not just use the rain jacket as a wind shirt when needed? My other thought on this is that it's rainy these days more than it's just windy...
also, for water, I've been using the Sawyer inline filter lately with my platy bladder. which is like the platy gravity system but without the need to have the extra bag. the flow rate is excellent and in theory you could take one and filter into your g/f's water container. I'd say it takes no more than a few minutes to filter 3L (my platy size). I've used this a few times for overnighters in the Whites and love the versatility of being able to collect water from any reasonable source. This last weekend I used it for the first time to filter water for the group and it was much more convenient than my steripen, the downside being you can't really fill a soft bag in a lake, you need a source that can leave the bag in air which leaves you with the small water falls in streams.
The filter is something like $25 through walmart online with a water bottle that I just "threw away".