Hi!
Below are two links, although I don't know if they would make your origonal trip possible or not?
If you go onto
P&O Ferries | Ferries to France | Cross Channel Ferries you will see that they sail from Portsmouth to Bilbau, Spain. This would save you a lot of miles from London.
Here is a link for a ferry company which goes from Morocco to Italy.
Ferries Morocco 2008 - shedule tariffs and informations for all the ferries to Morocco
Personally I think that you are trying to do too much! We were away for 17 days this year, 15 of which were in Germany (mainly), we did 2066 miles, avoiding the motorways as you will definately not see anything if you use them. If you do use the motorways you will have a BMW perminately 5 feet away from you... this is not my idea of fun! We had 2 days off the bikes which were much needed... something which I don't think you've allowed for!?!
We found nothing worth stopping for in Holland (maybe someone could suggest somewhere?).
Last year we went to Belguim, found some nice places although mainly in the south. Brugge is nice as was Bouillon and a few other's which I've temporarily forgotten the names of.
If you pass through the Harz Mountains in Germany then the medieval town of Goslar is worth a look, it will be on your way to Berlin and possibly a better lunch stop as it is smaller and easier to get in and out of. Other highlights in Germany include Schwangau, the home of Neuswanstein Castle and the Alps. Black Forrest and the Rhine and Mossell Rivers.
In the Czech Republic, Prague is definately worth a visit. Although... what can you see in an evening after a hard days riding? How much energy will you have left?
Hungary is also a nice country but the capital Budapest has western europe prices. Lots of nice turkish baths which are great to relax in and I remember eating nice cakes. If you are a Hayfever sufferer I also remember that there was stuff flying around that looked like cotton wool which resulted in me losing a day!
Austria - got caught in a sudden galexy minstral sized hail storm when we popped over for a ride this year-, Italy, Slovakia and Romania are on our list for next year but can't really tell you much about them. Although... remember that on Lake Como in Mandello del Lario there is the Moto Guzzi Factory & Museum which may interest you? I believe that they do a tour only at 3pm everyday and that it is not in English but still worth going to.
Also remember to take your waterproof's... when it rains in Germany... boy does it rain!
Let me know what you decide for your final route and happy planning!
Beej