I finally figured out why saidit's front page always feels stagnant. I realized that it's tied to the other difference I noticed from other sites, is that 70% the time that you post the post gets zero votes, no matter how sure you are that it's good content and it did well on other sites (yes I post to a few places).
The difference is that nobody on this site browses /all/new. Why don't they browse /all/new? We all know the reason why.
That means what succeeds and what doesn't is more probabilistic. A significant amount of content never goes into the running simply by random selection