I have a 26" Innova on a 12' frame. The frame itself, front to back, is 52", and when the machine head is all the way to the back it extends about another 12", so that's 64" that is required just to fit the machine in the room. Now the distance you need to work depends somewhat on your size, but I would suggest at least 24" on the front. Most people will need to walk behind the machine even if you aren't doing pantos. You need to be able to change thread, clean the rails, clean the encoders, etc. You could probably do those things from the front or side of the machine, but it's much easier from the back. So another 12" on the back is nice to have (since you already have 12" beyond the frame because of the machine's movement). That's a total of 64+24+12=100 inches, which is 8' 4". I have more than that on the front, and the back looks out onto a large room, so it doesn't feel closed in at all.
I would not be happy with an 8' frame, but you might be if you do only lap size quilts or art quilts. I have used almost every inch of my frame on kingsize quilts.
I highly recommend Innova if you're still looking.