This will depend a whole lot on the child and their peers. For a fairly young child, there's a lot of future value in knowing a few activities well enough to know if they want to pursue it more formally as a pre-adult. For a child old enough to have (slightly) informed opinions, your best bet is likely to let them pick the topic and you provide the balanced discipline to decide whether to stick with it or switch during the tough periods.
I expect the variance in expected value between different activities is much smaller than the variance of good fit for the kid's context.
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