Enhancement: Auto-suggest a difficulty level in the Chart Editor

[IDiMooo]

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What is your suggestion, and why should it be implemented?

The new Difficulty Level feature is pretty cool but can be tricky to set on a difficulty level on your own. What if there was a formula that could atleast make a proposition for you.

I personally use something like this right now: (total notes * 500) / (length * 0,01) / 20 000 = difficulty level (rounded)

It sometimes matches vanilla songs but sometimes doesn't but yeah it just gives you a proposition of what your difficulty level could be.