I'll say this much, King definitely seems a lot physically stronger than Doffy at least.
Doffy was shown able to physically break through Luffy's defences in base, sending him flying on several occassions.
Doffy also sent Luffy flying with his kicks on several occassions that caused significant collateral damage to the palace.
King has been shown to not only break through Zoro's defences this chapter, but also to completely overpower an attack to do serious damage.
I think thats definitely solid portrayal even in comparison to other emperor commanders, especially considering the overpowering in the direct clash, and just how far he sent him flying afterwards. Definitely makes King a solid first commander physically at least(not accounting for his fire abilities).