My initial feedback after my first five minutes checking this out: a huge amount of sites I get only display this. Overall, all the sites it "stumbles upon" seem to have a very strong bias towards STEM topics, history, etc.

Nothing wrong with that at all in my opinion either, but many tend to be at a level that might require quite a bit of familiarity and/or studies that could be daunting for Joe Blow to even get why they are interesting or neat. Maybe the focus could be broadened somewhat, perhaps with a feature allowing me to select some baseline topics I'm interested in first, tech, video games, etc. As it is now, it doesn't feel particularly 'random' and many of the links aren't super 'casual' on first glance. Funnily enough, many of the sites that don't allow Cloudhiker here are really only where I'm seeing the quirkier stuff.

I'm not a programmer type, sorry if I can't really explain it more coherently than that. :)