I don't think opportunities to make choices are usually considered to be in the domain of a utility function. (If I'm wrong, educate me. I'd appreciate it.)

This would be entirely true if instead of utiles you had said dollars or other resources. As it is, it is false by definition: if two choices have the same expected utility (expected value of the utility function) then the chooser is indifferent between them. You are taking utility as an argument in something like a meta-utility function, which is an interesting discussion to have (which utility function we might want to have) but not the same as standard decision theory.

But the utility is the output of your utility function. If you're not including the risk-aversion cost of choosing B in its expected value in utiles, then you're not listing the expected value in utiles properly.