Regarding footer links... Google more or less knows they are footer links and treats them as such. If it doesn't make much sense to have so many links then don't. There are better ways to drill down to crucial content that is not one click away from home page nav in general (e.g. content!).
URL length does not matter, but it's good to have a nice hierarchy for clarity (much like breadcrumbs) - however I have noticed an interesting thing... when you do site: Google (among other things) sorts site pages by URL length, starting from shorter down to longer URLs. Does this impact rankings? Maybe. How much? Probably to a tiny digree if at all.