First offence: 7 days
Second offence: 14 days
Third offence: 30 days
Fourth: Permanent ban
About your suggestion; While deleted post usually means it's spam, making a general rule regarding that may not be advisable. Some users complain of their bumps being deleted wrongly or their replies getting deleted mistakenly for some other reason that isn't spam.
I believe it's best to handle each case uniquely, rather than taking a general approach.
Thank you very much, wasn't aware of that rule. And you're right deletion might be harsh sometimes so it's best if there is a rule in place to do its work.