Love the pixel look, and the pack-smashing idea is fun.
On your first question: we tried the opening three times and didn't smash a single pack in the first 15-second round. The packs drift out from under the ring before the outline fills. That left us at $0 on the upgrade screen, where Round Time costs $1, so there was nothing to buy, and we never got far enough to fill a Slot or see an evolution.
An idea: make the first pack of the first round sit still in the middle, or make it fill faster, so every new player gets a Beast in round one and sees the team-building loop right away.