I anticipated this would happen:
Sorry but this solution seems easy to circumvent.
It's much easier: in my self-moderated topic, I can't delete
my own post, but I could delete
my alt's post.
The only complication for the bump bots will be to attach a bot to the account that created the topic.
A possible solution would be to reject any user from posting in a self-moderated thread after 2 or more of his posts have been deleted. That would be a nice feature for legit thread owners too.
This could solve it:
Suggestion
Would it be possible to ignore Newbie-posts when sorting on "Last post" in the Altcoin boards? That would make it impossible for a Newbie to bump a thread (while they can still post). If needed, this can be increased to higher ranks too.