So...what were the first 8 plans?

I'm not sure of them all, but I've heard several involved impregnating a bunch of your Earth "females", as you call them. But when it came down to it, they just couldn't perform under pressure, so they just decided to create some zombies instead.

Im not sure but im pretty certain 8 more of these movies would have been an awesome thing;)

If you watch the Rifftrax live version of this movie, they actually have a song about this very topic!

They didn't work

[Elaine, George and Jerry are going to see Plan 9 from Outer Space]

Jerry:
"Elaine, you don't understand! This isn't plans 1 through 8. This is Plan 9. This is the one that worked. The worst movie ever made."