Nothing ridiculous about the Penguin except the way he looks.
From his very first appearance he was a stone killer, who actually managed to escape scot free at the end of his debut.
Yeah, Penguin embodies themes of corruption, cycles of abuse, and misanthropy. He's disturbing, not ridiculous, not once you scratch the surface even slightly beyond his appearance.
Penguin: Pain and Prejudice is a pretty good model for how Mandarin should be fleshed out. Of course, Mandarin isn't deformed(though he may suffer from acromegaly, depending on the artist) but because of his aunt he was basically treated like a cross between how Penguin was treated, and how X-23 was treated. The abuse was to create a super-soldier, but it was still abuse. (Also, a half white kid suffering from acromegaly wouldn't have been treated well in old China, assuming a writer wanted to run with that on-again, off-again aspect of his appearance)