we got back early this morning - and found quite by accident that on Sunday there were loads of characters out at 5pm when the parade was on, near the fantasy festival stage in fantasyland. We also found characters just after the parade near Colonel Hathis in Adventureland on Saturday, and yesterday after Cars n Stars Cruella and Gaston were out and about near Hollywood Boulevard for about an hour. On Saturday from around 12noon for about an hour the stars of Cars n Stars were alternating in the Studios around the main stage, Hollywood Boulevard, Animagique and Flying Carpets, but we didn't see any on Friday or Sunday at the same time.
I, like Davewasbaloo, do prefer the surprise element of meeting characters and we rarely do the queued ones. Having said that, until yesterday (our 5th day) we did think we'd seen less characters around the park - but we caught the good morning character thingy and there were loads of characters in the vehicles (I'm counting in my head now ........ 15 that we saw).
My niece counted her autographs over the 5 days we were there - she got 39 (this included about 12 from our 2 character meals).