A question -- to what degree should these stories be open-ended (or not)? I think you've mentioned before that you don't necessarily want an origin story from the get-go, so I get that. But I assume you also don't want me to kill the main character, right?
I'd like the 8-pagers to be self-contained stories that could take place within an ongoing comic.
For example, picture a single 32 page issue of "Batman" where the Joker takes hostages, Batman takes him out, and there's a happy ending.
That doesn't mean this was the first - or last - time the two clashed. It'd probably find a clever way to get new readers up to speed with something like: "The Joker? He's an unpredictable killer. This is going to be a long night." but other than that, we don't need to know their respective origins and ALL of their idiosyncracies.
That's what this would be, but take those 32 pages and squish them to 8.
It can be done, the stories would just have to be a bit "honed" in focus, etc.
For example, "The Quiz" is about a college age hero who retains all knowledge. The trick is that he has to KNOW it in the first place. He knows everything about executing Kung-Fu moves, but he still had to learn it. He could also read through a phone book and match phone numbers up with random names you shout at him.
We don't need to know the how and why right away in the "Breakthrough" anthology. Instead we'd perhaps focus on a man who is murdered by a mystery killer, and see that The Quiz is brought in. At first it's because he would know something important to the scene of the crime, but it ends up that he steps into the room and immediately starts to notice the things necessary to put together the killer's identity. There's no epic chase, no fight scene at the top of the bell tower, just a setup, some dialogue, some crime solving, and a "take him away, boys!" when the killer is revealed.
That's something that easily fits into eight pages.
The logos and story rundowns you posted at DW (which are totally cool; you should post them here) sounded like the sort of thing that could expand beyond a single eight-page story. Are these eight pages required to have a defined intro/conflict/resolution, etc.?
Yeah, once the "test" page replaces the current placeholder at incomics.com, there will be some nice stuff to look at and read.

Heh.
But yeah, ideally these stories would set up future installments, but they should be contained in 8 pages in case that never happens. No cliffhangers where people feel cheated, etc. I wouldn't rule out killing the protagonist, but it'd have to make sense and avoid 'pure shock' status.
I really want to emulate a sort of "Stan Lee era" on this thing, and while I'd give loose guidelines and try to be somewhat hands-off, I'll still bring the "Why exactly do you want to kill off this character, and what will it do to positively or negatively affect the story?" stuff. Heh.