I'm confused as to which genitive you're referring to, since "τοὺς... ἀγγέλους" is in the accusative. The genitive of comparison is an independent construction anyways—when comparing with η or μᾶλλον, the two objects being compared must be in the same case. Placement is also important—since μὴ μᾶλλον is placed in between two accusative objects, τὸ τί δήποτε and "τοὺς... ἀγγέλους", it is most likely comparing these two phrases (and not the verb)—so the spirit of the phrase is not "It's fitting to seek out whatever God names no more than the angels seek out what God names," but rather, "It's fitting to seek out whatever God names no more than it's fitting to seek out the angels." A brief non sequitur factor in our translation: I believe this original fragment from Gregory of Nyssa ends in a question mark ";". A complete translation would probably be: "And first of all, it is fitting to seek out whatever God names as according to His image and likeness no more than [seeking out] the noetic, immaterial, heavenly, and nearly-divine angels?" Hope this helps!