I'm feeling some inspiration from Inscryption here and loving it. I really like the potential of this game so I have a load of suggestions that you can do whatever the hell you want with.
In regards to an earlier comment on flattening the difficulty curve:
1. A mode with just one pill per frog
2. A mode with only two frogs
3. A timer bar as it's hard to gauge how long I have, and as the round automatically rolls on it feels easy to become left behind
My initial instict was to press W to place the pills, I'd say a control scheme as follows would be my ideal.
A /D - move left/right
W - place pill
S - skip currently queued pill
Some minor changes:
The controls menu is missing a key for Select Pill and Place Pill and automatically clearing pills after a failed round would be a shout.
Hopefully this helps, genuinely sick job on this!