Mace really doesn't have anything to compare to humiliating Ventress like Vos and fighting faster than Dooku. Vos even when poisoned by a snake's venom was capable of fighting Ventress off in a duel when she was amped on Dathomir in their first fight in the novel
Mace struggled with her in canon, whereas, Vos utterly destroyed her in their 2nd fight when he first embraced the darkside:
I thought their relationship was convincing (as it developed), you should read the book.
I also don't see Mace as being that much more skilled if more skilled than Vos at all at this point. Without his Vaapad amp Mace really has nothing other than accolades putting him on par with Quinlan at this point.