Sylas' original intention wasn't to create an Armor so powerful. This easily placed the Serpentes Armor on a level all to its own compared to the others.
Its Layers didn't even remotely reflect what it had once been. It was like it was a completely different Armor entirely. Part of Sylas even hesitated to release it back to The Sanctum.
This wasn't because he valued it so much, he hardly cared. He had created something like this once, he could certainly do it again. In fact, he would surely forge something even better in the future.
Also, the Whale King Armor, despite not incorporating any Sins, was no less powerful. After all, its creation was built on the back of Fathomless Rune Creation.
The real reason was instead that he didn't know how this sort of thing would impact the Serpentes Lineage. It might make them very strong… but it might also destroy them from the inside out.
