I just looked at your planner and find it very attractive. One issue that I see, if I understand this correctly, is that you only get access to the FAA briefing material AFTER you file the flight plan. I would not want to use the planner if this is the case, because I base my plan (departure time, fuel loaded, and route) on the expected weather. I do not want to file a plan until I have seen the briefing.
This has been requested before and is coming; at the moment we’re working on more pressing things like RAIM.
Dang, sorry to hear this…
Weather / NOTAMS to me way more important then RAIM GPS outages unless I am really missing something in my briefings???
Always up for learning (wondering why RAIM more important then weather) 
You get the weather briefing after you file, and you can always file again for another time, no harm, no foul.