Hi Christopher,
I can’t find that request and 77505 is not the right number, but we did have a request for this internally and I’ve added you to that now. It makes sense to be able to do this with bubble charts like you already can with ‘bubbles’ on maps, etc., but historically bubble charts have not normally relied on this and it had not been requested yet. Even with a legend, intuiting the values associated with varying sizes is always a challenge and tooltips are probably the best bet for making sense of a particular size.
Since bubbles are sized relative to zero, the main value of interest might be the largest one. To help make sense of the values you might try displaying this in a data label, or use states to display it on the largest value (where it equals the result of the TOP formula).