The breath of a wounded lion is far more terrifying than it's roar.
As I was working on this, I was thinking of a backstory in my head: that after the Gundam Wing Endless Waltz events, either Zechs or ( Heero now that the zero suit is kaput) can't come to terms living in peace, so they go off lone wolf with the Tallgeese to battle remaining stragglers of the army - without support/funding/etc (now that the Earth and colonies are at peace, they want nothing to do with cleanup fighting) and so the suit just gets more and more banged up and poorly patched with whatever they can manage.

https://www.deviantart.com/chasingartwork/art/Tallgeese-III-860221023