Advertisers (and most publishers!) are unlikely to agree to this proposal as written. In particular the restriction that only the first party site can set up campaign identifiers makes it difficult for anyone other than a major publisher which already handles their own advertising (Facebook, Google, etc). The fact is that most sites don't have a direct relationship with the advertiser, so it just won't work for 90% of publishers.
I'm saying they can't get attribution from this unless they are a major publisher. There's no choice there. This essentially means that bigger companies (that do direct advertising) can make more than double the revenue from ads as small companies.
Of course the small publishers could let the ads networks host their content (in an iframe?) to recapture that revenue, but then we end up in a worse privacy position -- as there only end up being a few hundred first party hosts on the web that host all of the content and can track you with first party cookies!
