My opinion has actually changed, I think I would buy links in articles on newsy sites or blogs, anything with decent traffic really, because I seem to get quite a bit of traffic this way these days. From being mentioned in news articles. I'd suggest links that will stay forever, and do pass juice, just because they're preferable to expiring links that don't.
You might also go for a banner on a medium sized site, though I don't know if that would work as well.
Content is a great idea, but I generally try not to suggest that one, else I appear insincere. The more words you have floating around the more keywords.
A consult could be a good idea, there might be some traffic streams that you are not utilizing.
As Mike said, Press releases, These are good for traffic and backlinks
