Lucky cine club! Thanks for the great tips.

Edgar, noooo! It can be very, very frustrating, and many of us can relate to what you're feeling. You might appreciate hearing that on the panel, Tess Greenberg said she spent 10 whole years working in documentary before realizing she hated doc, and wanted to do comedy. If you still haven't found good collaborators in another year, you could always try starting fresh in another vein of filmmaking!

By all means, do something interesting with your life! I'm certainly not advocating otherwise. This is what the film industry is talking about on the ground at SXSW. Take it or leave it as it fits with your career goals.

I’d say shoot 1080. My impression with the 600D is that, while it takes pixels from the full height of the sensor to shoot 480, the data transfers at a such a lower bitrate that you’re losing more than you would shooting at 1080. (On the 5DMkIII, for example, 640x480 mode only allows IPB mode/10 Mbps; 1920x1080 offers ALL-I mode/90 Mbps. That’s 9 times less data for a frame that’s only about a third smaller, give or take. So it's getting more compressed. If anyone else understands this better, please chime in.)
Also, since you’ll be editing one timeline with both 1080 and 480 footage, having all the clips at the same FPS and resolution would make it that much easier. I believe without ML or firmware on 600D you can only shoot 640x480 at 50 or 60 FPS, whereas your 1080 footage will be in 24, 25, or 30 FPS. Shooting everything 1080 and cropping in post, you don’t have to deal with mixed FPS.
So I’d say go for 1080 and modify your monitor any way you can (tape?) to frame it for 4:3 while on set! Amman did say that was crucial for composing shots on ‘Dayveon.’ Good luck! Sounds like fun, would be curious to see the film when you're done.

It's from the midnight short "A Nearly Perfect Blue Sky" that's mentioned by Emily Doe below.

I haven't had a chance to see the Adam Curtis film yet, but will be sure to now. Looks frighteningly fascinating. Thanks, Ed!