I think DR Harald feels a bit weaker than DR Rocks did, but overall he was amped for sure and Loki was highly comparable to him at the absolute least.
Imo the main threat of Harald was his regen, he'd lose to Loki in a fight but he'd keep healing and getting back up over and over while Loki would tire out eventually.
Also I can't see your original post's text in the light theme for some reason. Think your font colour is the reason why.