The presentation really makes this shine.
Finally completed the game on hard (after maybe 6 attempts - 2 today, at least 4 yesterday). 46890
The world falls into place before our eyes. A desert is transformed into a vibrant grassland, with hills falling into place as if they were children's toys being dropped from just above the screen.
The train steams past, containing the Doeos; Doeos form curvaceous patterns in the sky...
The difficulty settings were exactly what they said on the tin - I tried 'easy' first, never feeling that I was in danger of failing, yet thanks to the style of the game I was forced to remain an active participant. Hard, on the other hand, really did feel like a challenge and kinda forced me to learn the patterns.
I played the flash you cited and feel yours is an improvement, thanks to the greater prevalence of changes within any area. Yours feel more alive - specially the commentator level when we fly up and the train level after the crash. Little things like buildings opening add up and the 'intro' at the start of level 1 certainly helps.
One mechanical improvement is that in your game, the Doeos seem to last for a more defined period of time - with a few exceptions, they remain on screen for roughly equal amount of time, the blue Doeos being a visual indicator that they will disappear sooner.
I'd have liked to see some visual indicator of when they'd disappear, or maybe have them all last EXACTLY the same length of time - with a one or two additional colours lasting differing times to give you freedom in design.
The mechanics are fairly standard when all's said and done, but your presentation really made this - the lovely graphics, the inventive world and the music.
It seemed a shame that the 'replay' screen seems to be like an afterthought, lacking the excellent graphic design sensibilities shown elsewhere.
One question - what's the 3rd flag? Blue with white circles. It seems to result in Japanese text...