I mean, he's literally sleeping with all of them. That feels like it can't get much more fanservice-y. Had he treated them all like sisters instead of wives then it would match up well, but as it's currently done all I can think is this guy is the end result of some harem romcom where the writer couldn't make up his mind.
Yeah, but how is putting a female a "fan" might find attractive into a relationship with male "competition" more fanservicey than putting them into a relationship where no man is included, and all one's fantasies about their sexy life is just a mess of a buffet of T&A? Wanting to see a bunch of women get it on between themselves is generally a peanut gallery-style lusty desire, regardless of if the characters are hetero or homosexual.
"They're all taken, and they're all happily devoted to one man!" is more of an anti-boner set-up, I'd think. And the fact that any suggestion that someone else might be good too, was met with "Yeah, but DARLING is the best!" also seems like anti-service.
Looking up more about
Harems in general, I do wonder about the hierarchy of his now. Amida is said to be his "Primary wife", Lafter is just a "girlfriend", I wonder if some of the women are less bed-buddies, and more nannies and stuff?