Discussion on answer by Thomas Ward: Found SSH Backdoor on VServer. What to do?

Don't get me wrong, adding more possible values per character by adding numbers and uppercase letters etc. also makes it harder to calculate a password, of course. But each additonal character in length easily outperforms additional variations per character. Mathematical example: 26^2 = 676 (that's lowercase a-z, 2 characters long), 104^2 = 10,816 (that's lowercase, uppercase, numbers, special characters), 26^3 = 17,567 (that's lowercase a-z, 3 characters long).