Aren't we all?
It should run on a Zero, can't see why not. Depends on which nodes are running. Something trying to map gigs and gigs of data might need an external swap space but you can do that over a network.
It might just be a bit slow is all.
Basic ROS stuff works just fine.
I will be controlling an AlphaBot 2 wirh my ROS install. I will write some python or C ROS pacakges for the specific motor controllers if anyone is interested.
...btw 5 hours is compilation time. It did take me 3 days to get to a build that didn't fail
... As for Serval yes, slowly but surely it is progressing. I have field tested the latest stable release on Android in rural conditions. They are field testing in Vanuatu at present.
Maybe the Orange Pi is better suited for Serval with its Android implementation.