On the topic of a private crawl (or distributed crawl), these are cool ideas, but not something we currently have in our plans. Having the crawl centralized allows us to store historic data and ensure polite crawling. This may take a little extra time (we are indeed doing a lot of crawls, as well as processing them and retrieving link data for each of them), but we are actively working on on our infrastructure to reduce our crawling and processing time.
While the first crawl does take a number of days, subsequent crawls are started on the same day each week, and should take roughly the same amount of time to complete, controlling for external factors. So in general you should have fresh crawl data right around weekly, give or take a day or two.
As for your specific crawls, I'd be happy to look into them for you. I'll send you a separate email to discuss.