Be aware that PP is less structured at DL and DCA. Photographers may not be around or there may be a lot around -- it just depends on the moment! And they are not allowed to ask you if you'd like them to take your picture. You need to ask them (that's just the rule at DLR for some reason). So if you see a PP CM standing around, go ahead and ask for some photos! If you see a character at a M&G without a PP CM (this can happen), ask a fellow guest to take your photo and offer to reciprocate. Just don't worry if you don't see as many PP CMs as you expect -- they are out there -- just keep looking!
More good photo spots:
BVS -- by Carthay Circle fountain: Mickey, Minnie, Donald, Daisy, Chip & Dale, Goofy, Pluto, etc.
Cars Land entrance by the billboard
Cozy Cones -- Mater or L. McQueen
Sometimes by the Cars Land Arch by Pacific Wharf -- lovely photos here in the evening
Sometimes by the plane by Soarin' -- usually with Pluto