How to find out my site is being scraped?

I've some points...

1. Network Bandwidth occupation, causing throughput problems (matches if proxy used).
2. When querting search engine for key words the new referrences appear to other similar resources with the same content (matches if proxy used).
3. Multiple requesting from the same IP.
4. High requests rate from a single IP. (by the way: What is a normal rate?)
5. Headless or weird user agent (matches if proxy used).
6. Requesting with predictable (equal) intervals from the same IP.
7. Certain support files are never requested, ex. favicon.ico, various CSS and javascript files (matches if proxy used).
8. The client's requests sequence. Ex. client access not directly accessible pages (matches if proxy used).

Would you add more to this list?

What points might fit/match if a scraper uses proxying?