A summer frog festival is a fun and unique way to work the theme and the music fits it very well!
The trumpet VST you used especially is perfect for this theme.
The whole OST is just oozing with whimsy and charm that you can't help but imagine the frogs in their little band gear playing for a festival. I imagined it looking like the Princess and the frog (which is my favorite Disney movie) so I quite enjoyed it.
My favorite was probably the band master or a froggy fair because of how much charm they had.