Do the balloon colours mean anything?
Solution 1:
I don't have any definitive, data-mined data but I've shot over 300 balloons so far. I can confirm the anectdotal information from several guides on animal crossing balloon colours:
Any balloon can contain anything. I've gotten furniture and clothes from all colours of balloons.
But yellow balloons are the only ones I've seen to contain bells, and blue ones often carry crafting materials like clay, iron or gold. I can't remember shooting any blue, red or green balloons that contained bells.
There's still some difference between guides on what red/green balloons contain most, I did notice all of my recent seasonal DIY recipes came from red balloons. But since they also often drop furniture for me, it may well be those are the ones you mostly get furniture from.
I know of only two balloons where the color would tell you something about the present: The bunny day balloons that dropped sky eggs, and the golden balloon that gives you your golden slingshot DIY recipe.