I may have been somewhat harsh in regards to the GBA armor knights. While their armor is still bulky, it doesn't look quite as bad in official art where they have the shield off. Here's Blazing Blade's Oswin for reference:
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And here's Binding Blade's Gwendolyn, who serves as the only art for a female armor knight in the GBA games:
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They are definitely designed to look like the “big guys” of the team with their plate, especially by comparison of cavaliers, who also serve as knights but wear lighter armor to show that they aren't quite as tough. Blazing Blade's Kent for reference:
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