Do you want to change individual weighting for the questions, or rather specify at the beginning something like "this startup is in the B2B space, therefore sales will be the major challenge", or "R&D will be critical", etc... I don't see how you could weight questions, but you could weight high-level sectors. Does that make sense?
Ultimately, as a geek, I want to see what makes the thing tick, and think about how that may or may not relate to my situation. Also, unless you have access to statistics that most people don't, your numbers may simply not be any more accurate than our own estimates.
Making it spit out a google spreadsheet or something would be a neat trick.
