Im not much on object composition... I leave that to the photographers. But in terms of colour I think it could use a bit of a bump up for the foreground.
At the moment what you have is a grey foreground, with a bright background at the bottom behind the foreground, then a dark background at the top. The eye is drawn a bit to the bright sunny part of the background and the balloons look dark by comparison. If you want them to look like typical bright balloons then you want to minimise the effect of the bright background by darkening the background, brightening the foreground, or both.
And for the spray of droplets in the air above the balloons, Id either hit them with a bit of contrast or a bit of blur to make them stand out or blend in (depending on which you want). At the moment theyre kind of in between... theyre visible but not very distinct.