> Pure brute force is a bad metric, every 12 character password is equally good or bad by that standard.

This is not entirely correct. If you had 12 q's in a row (or any 12 lower case letters) there would be 12^26 permutations that computer would have to check in order to guess it. Adding a capital Q would increase the number of permutations to 12^52. For each additional character set you throw in the mix, you would add the total number of those characters to the exponent part. Adding numbers would make it 12^62 etc. Not all 12 character passwords are created equal and some (like 12 numbers in a row) can quite possibly be brut forced.