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You could try Wox for it's more expansive capabilities.

For file search you could try Everything published by Voidtools.

Does it have the same easy to pull cmd+space type thing? I really like that it's always there no need to open an application.

Wox has a preconfigured hotkey.

Everything allows you to set a preferred hotkey in the settings.

Everything is the tool I miss the most on Mac, I haven't found anything even close