User blog comment:GrilloSama/Commander Thatch/@comment-24792841-20171107145317

Strength as a commander? Sure.

But, how strong is a commander? Let us draw an analogy from the other Big Mom's crew.

Big Mom: sweet commanders - stronger than most rookie's; ministers - comparable to rookie's (but really depends)

Hence, I guess, he may be comparable to rookie's but really only in the mid-levels.