As a lover of platformers I like very much this game, you can feel the trill in every jump. Or should I say every flight?. the controls are rough but good enough to handle, reminds me of nes games, the graphics and music feel so nostalgic and calm, is relaxing maybe a bit sad. I don't see a real problem with the lack of checkpoints, personally, I think the objective is enough clear from the beginning, the motivation to go on, discover checkpoints and the amount of them are good, in conclusion, great game, few mistakes.
P.D: I passed through the first wall without considering there where a platform below to open it.