Nah, snow still works. There just needs to be some other indication that there's snow. Like some snow on the hills in the background, for example.
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things that can be reasonably inferred from the level design, so they're particularly out of place here.
While "Grab Key" is out of place, "eat it" isn't. It's new sprite, and player may not know that it's possible, because not all sprites eatable. Player may realize it after key flying away, and I try to explain what player (or level designer) can do with it. Being able to eat key is feature (?) that isn't common for everything.