Anyway, if this is including all of Hett's feats including holding a slight edge over slightly post ROTS Kenobi albeit with a little environmental help then he murks. If this is younger Hett, probably Darach.
Holding a saber tip millimeters away from his chest when both of them are stopped. Sidious allowed Mace to fight.
Sidious let himself be disarmed, and canonically feigned weakness in the Lightning. This was against a Mace whose powers had a massive circumstancial boost. Even boosted Mace was getting his ass kicked by Palpatine's Lightning as shown in the novel- Palpatine only didn't kill Mace because, as stated, he was feigning weakness to turn Anakin over.