Do a mini marathon play x games cough *Yoshi* ones from 6am to 6pm type thing. Or whenever the sun rises and goes away. I think its more of a style that would be better for you. No falling asleep or being a zombie and more importantly hopefully you wont run out of things to talk about.
Also another thing is to get a cat. Nearly all I have watched have had a cat or some little dog. People like cats, so borrow a cat. Or one of you dress up like a cat.
We enjoyed having the Let's Plays done and up on our Youtube, but the amount of work that had to go into them was getting to be too much. We wanted to try out some different stuff to see what we liked and enjoyed, and while we enjoyed doing the Let's Plays, the editing was a lot of work and in the end there wasn't much return on investment.