I like the idea of being able to narrow down what you get from the wheel by choosing what to sacrifice, but I think it would be nice if you could choose specifically when and where boosts would activate . . .
i agree with this opinion. it would really be more meaningful if you can store the reward for use later. also i guess there would be a co-relation between the worth of the sacrifice and the worth of the reward. though a small sacrifice might produce a great reward, if the reverse is true, then high worth material would never be sacrificed at all, and it reduces your options and the attractiveness of the exercise.