I did similar route in 2003, but in reverse to what you plan... but not Turkey, Greece, Hungary, Romania - I went North into Baltics, Russia and Scandanavia - but can reccomend Slovakia and CZ. So my experience might not help for Turkey, Greece, Hungary, Romania, etc - but I expect it's about the same
Places to see: Depends what you like - 'rough' camping is what I did and mainly spent time in the countryside - so head for mountains, hills, forests and lakes - I found it quite easy to wild camp in these sorts of places.
Ferry routes: Algerciras to Cuetta is a good route for Morocco - you just turn - buy a ticket in the town and your away - it's dead easy.
ATM availability: Loads around in most towns and all cities - you shouldn't have a problem. Just make sure you always have a few notes with you.
Camping availability: No problem - loads of choice - I aimed to stop between 4pm and 6pm and always found a spot which I didn't pay for.
Petrol availability - no probs - again most towns have a station, just keep it filled rather than trying to run the tank dry.
Hope this helps
(I'm quackers about bikes)
(I\'m quackers about bikes)