> when that link is posted to a non-porn subreddit it's more of a problem.

I think that's a seperate concern. Moderators delete bad posts, and the spam filter operates on a per-subreddit basis.

> Reddit is better as a community rather than a dump for links

I'd agree its certainly different as a community than say Digg, but I'm not sure if its for the better because reddit freezes out content creators from using Reddit to syndicate their content.

People posting links to stuff copied onto a pay-per-click image sharing site are pretty far down the food chain. What worries me is that essentially content-creators can't use Reddit without becoming a part of Reddit's community and 'paying their dues' as it is.

Reddit's mods and users have banned or severely punished even major newspapers who wanted to just post their articles on Reddit, and not become Redditors themselves.

Some of these issues seem like they could be addressed by in-house people at Reddit better than people on the outside - and I'm pretty sure they're already doing some stuff. One could identify clusters of users who 1) usually only vote for one another's stuff, 2) Vote up things most users vote down, and 3) Link mostly to 'bad' domains and rarely comment. These users could then be screened by hand, and hellbanned. This is the sort of thing that I would start with aberrant voting data though - and that is probably not public for the malicious bots.