There are two categories that have problematic identifiers. Would it be possible to rename them?
parsing— The name itself doesn't make it clear it's only about making parsers, and not parsing specific file formats. The description is clear about it, but apparently that's not enough: there are lots of miscategorized crates. I suggest
parser-toolingas in "tools for making parsers", to stay clear from incorrect "parsing (…file formats)" interpretation.
game-engines— It's too specific. There are many utility libraries related to game development that are smaller than an "engine" (e.g. just sprite or animation libs, maze generators, multiplayer networking, dice rolls, chess moves, game-oriented collisions or math utils). I suggest
game-devwhich is the industry's catch-all term.
I suggest keeping the old name as an alias for backwards compatibility (so a "game-engines" crate would still appear in the "game-dev" category), but showing only the new name to user after the rename.