If you remove the pardon system, you could also try removing perm bans for most offences. Perm bans would switch to 1 year bans for scamming. Direct blackhat stuff like hacking, mass-recovering accounts for profit, anything super-serious is a perm-ban. This should be fairly obvious and easy to distinguish. Something like scamming 20M on Runescape, recovering a personal Runescape account, and self-vouching become a 1-year ban.
If a user wishes to return after the 1-year ban, they must first repay all owed money to Sythe himself (with interest). A very select few Admins may use these holding funds to repay any direct victims from the scams, if they come forward with sufficient evidence. Money left-over will be simply kept by Sythe.
After serving the 1-year ban, the user will always have a rank / status which shows they were banned previously for scamming. This will make anyone who trades the user fully aware that they were previously banned for scamming. This also eliminates the need for a pardon system, and provides some revenue to the site through uncollected scam money. This should sustain any extra effort required in the system.
Many users on this site are between the ages of 14-17. They are still developing their moral compass. We should allow people a chance to redeem themselves.
In terms of ban evasion, the 1-year ban is applied on the most recent ban received by the user. Obviously, they will be required to repay ALL scams done by them on all accounts before returning. If a user who has had a 1-year ban re-offends after serving out a 1-year sentence, they will be given a 2-year ban.