The primary ability of the astronos is so broken, you can just be imortal forever if you have enough food, i think the starvation damage you take could be increased and health decraesed a little bit more.

I'd suggest slowness type of thing
Like whenever you would be invulnerable you could not more/you move very slowly and swimming is disabled
The ability also drains food, though as mention you can hold M2 with anything to survive, maybe making it so when you attempt to eat the ability disables itself?
Just a though

I also believe the astronos origin could use rebalancing.

They have been rebalanced. You can look at f880efa for more info on it.