First, as others have mentioned, the paperwork in Europe, particuarly within Schengen, is not complicated. In fact I've been riding there for years on vacations and have never been asked for any documents, ever. You probably know this already, but just in case, I wanted to mention that there are no border posts, etc. within Schengen, so you can roam at will over some pretty serious territory. That is not to say that you should not have appropriate docs, but as long as the bike is rego'd, you have some evidence you are authorized to ride it, and insurance, you'll probably be OK.

Second, I have no doubt that you could cover the amount of ground that you mentioned, but for me at least it would not be very fun. If you're going to super-slab around Europe you might as well stay in the US, cuz superhighways are pretty much the same everywhere you go. While I also enjoy putting in long days in the saddle, I don't usually cover much ground, because I stick to the smallest roads I can find. In Europe in particular this approach is really rewarding, and you end up seeing all kinds of cool, out-of-the-way, centuries-old towns, castles, etc. that you you never see otherwise. Obviously everyone is different and you should certainly do what you enjoy, but I'd at least consider a slightly more leisurely itinerary!

Third, I know you haven't asked, but if you are looking for areas to eliminate from your route, I'd consider Northern Germany, Poland, and Ukraine. I've found most of these areas to be pretty dull (with exceptions of course), and I'd probably try to spend more time in other places.

Lastly, from what I understand, bike theft is a big problem in many parts of Europe, so I always try to find some kind of secure parking at night (unless I'm in a really dinky town), especially if you don't have comprehensive insurance.

I don't mean to come across as being patronizing, but just wanted to pass on my thoughts based on my experience riding in Europe; your trip sounds great, best of luck with it.