As I mentioned in the other thread, I'm against fines because it is discriminatory. If we are setting a new a rule, it should be the same rule for everyone, regardless of wealth. There shouldn't be an option that allows those more well off to buy themselves out of a punishment.
Out of any of those options, I would be the least against a signature ban, but only for users that weren't obviously plagiarizing just to get paid from a signature campaign - these spammers should still receive an outright permanent ban. In those who do get a signature ban, it should be either permanent or based on them earning x amount of merit. I don't think it should be temporary - most would just abandon their account until the ban is up, which is no real punishment at all. They should have to work for its reversal. 100 merit is on the lower end of what I would go for personally, but I appreciate my views are probably quite skewed here. Perhaps @LoyceV or @DdmrDdmr could provide us with some numbers - how many users have earned over 100 merit since the system was introduced?
Another possibility to earn their signature back would to be make x good reports - this would need to have an additional requirement of >x% accuracy to prevent spamming the report button. Say 5000 reports with >95%?
Having said all that, my preferred option is still the status quo - zero tolerance.
Edit: Spelling mistake.