It's worth noting that penguin++ is currently the least used unit in the game, and has been considered 'extremely weak' for a very long time in the cycle form it shared with bombers, so if it becomes debate-ably stronger than pikeman for certain strategies I think that's actually a good sign and matches the intended purpose of the change.

Supposing the penguin buff is overcompensation, I think it's still unlikely to result in major problems since stacking multiple sources of freeze has diminishing returns (especially when the targets overlap), compared to stacking more attacks which helps to win trades.