Damn.
Gear 2 vs Doflamingo.
Gear 2 vs Hajrudin.
Oda needs to explain this.
I think it's pretty simple.
Dressrosa Hajrudin = strong and slow with middling Haki
Dressrosa Doffy = strong and fast as fuck with low-top-tier Haki
Now, Hajrudin has spent a lot of time fighting stronger opponents. In general, people Luffy beat, that try to continue their dreams after losing to Luffy, get a lot stronger. Don Krieg is in the New World now. Crocodile in Marineford. Lucci now has Awakening.
Hajrudin has speed/Haki issues, he's a smart/brave fighter.
IMO, that's what really separates Loki/Harald from other Giants, they're both very fast. When Hajrudin leaps at people, it's like this slow lumbering force, Harald would just pounce on your ship and crush it.
Honestly, one of the biggest nerfs to Hajrudin is that Harald was so focused on Elbaph itself, Hajrudin didn't get some of the training he needed, whereas Loki needed way less because he was born strong as hell.
Since Oda's teased Hajrudin getting a Devil Fruit back since Dressrosa, I think he'll get a strong one as well to match Loki.