Regular Antifreeze is a glycol based fluid and should help prevent rust and not harm rubber. Brake fluid. from my experience is also a glycol based fluid that is primarily made to withstand compression, not corode brake components, and not breakdown with heat - yes it does remove paint when left on a painted surface.
Farmers use fluid in tires only for weight - water would work by itself, but would corrode and freeze - therefor a water anit-freeze mix is used. The people who use salts in the water are achieving 2 things - one is a lower freezing point and two is more weight - saltwater is more dense than just water - and a tube would be used to keep corrosion down
I like the idea of using straight antifreeze - if you were worried about the environment, maybe some RV antifreeze, although I don't know about it corrosion inhibitors.
BTW, I would recommend corrosion inhibitors even if you have aluminum wheels. I have seen our city water consume aluminum fittings in our cooling system at work.