Sooooo, this is basically just a fight chapter. But it was fun to write!
And yeah, Link was not using anywhere near his full potential. Which is not an insult to Eddard.
Eddard is a damn good fighter, one of the best swordsmen in Westeros. But he isn't as powerful as Link. And that is okay.
Link is insanely powerful, capable of stopping a fully charging Lynel in his tracks with a single shield swing, and is able to survive insanely powerful attacks, explosions, and even lightning strikes as he regains his strength through the series.
It's like Eddard is John Wick and Link is Spider-Man. Both are badass, but one is superhumanly powerful.