Glad you liked the game! I know we had a ton of fun working on all the distinct frogs and various features to give it that extra bit of polish.
As far as balance goes we sort of ran out of time to work on balancing the game towards the end of the jam. I don't think any of us knew balancing a tower defense game could be so much work :P
We have a lot of updates and bug fixes ready to push and patiently waiting for voting on the game jam to end :P
It's a shame we couldn't get those fixes out in time but such is the nature of game jams