I agree on those complexity graphs since they're actually scanned from Sean Carroll's book and edited in Pixelmator - if I was better with graphics I could probably recreate them as SVG or in an editor and make it only a couple kb.
Same for the MinutePhysics screen grab, though I couldn't bring myself to attempt a poor recreation of their work and couldn't get rid of the weird pink gradient background which probably prevents better compression.
The Youtube cover images are still being pulled in from youtube - I debated downloading/compressing/hosting them myself, but figured I'd gain more from downloading them from the separate domain since I still think there is a default limit of connections the browser will open to a single domain at the same time.
That page includes images and "embedded" youtube videos, but loads 454kb of 3,187 words with 10 requests in 450-600ms - if anyone has any suggestions on how to reduce that further, I'd love to hear.
Going to bookmark that txti.es service for the future, definitely seems useful for publishing simple content without needing to fit it into a blog theme.