Trending seems to be dependant on the daily performance, and doesn't require that much; my series popped up in the trending section a couple of times (that I'm aware of) and it took only four new subscribers or so, each browsing through about a half of the comic.
On the general topic, I do agree that a fresh section, maybe beneath the Staff Picks, would be nice, for readers too. Many times my eye was cought by an interesting thumbnail and I discovered a series that I like, and the chances of that happening increases greatly if you don't have to go browsing an entirely different page. It's the Prego Spagetti Sauce principle: people don't know they want to read a new comic untill they are presented with it.