I think part of the problem with reporting posts and getting them deleted is that it isn't really a punishment. A spammer can easily churn out a one line shitpost in under a minute. Even if 50% of their posts are getting deleted, they can still max out their bounty campaign easily enough.
One easy solution would be to remove any merits associated with a deleted post. I'm not sure what the "knock-on" effect of that would be though. What would happen if the postder had awarded the sMerits associated with the deleted post?