I've been having lots of second thoughts about upgradeable zoom myself, it really ruins the size factor of massive asteroids. I'll probably scrap it altogether and set the default zoom value to an equivalent of one or two bought sensor upgrades.
I've gotten lots of similar feedback about the controls being hard to deal with, but I'm unsure how to amend that while preserving ship inertia for that semi-realistic feel. Would higher linear velocity damping values help?
I would also like to know which difficulty were you playing on. On easy and medium, asteroids move significantly slower than what I originally intended, but maybe I should also reduce their right-side spawn probability,, that will definitely make things less chaotic.
As for the tractor beam, do you find it unreliable because a crystal you're using the beam on can miss your ship if your lateral velocity is too high? Again, I don't find that unrealistic and upgrading the tractor force should definitely help with that, but since it appears to be a constant source of frustration, I will tune its values a bit.