Harem stories (including reverse harems) are a guilty pleasure for me, but I'm picky about how it's handled. I want the harem's leader/focus to have emotional relationships with each of their gals/guys, and if the connection they felt with the first gal/guy gets lost as others get added I am disappoint. I also want all the gals/guys to have relationships with each other β not necessarily sexual or romantic, but I like to see how they're all in this together. They all have to live with each other, after all, and have both good and bad moments.
Which means when the harem gets "too large," it breaks down for me. Let's face it β it takes a really good author, with a deft hand at characterization, to juggle an ensemble like that. The largest I've met that fully worked for me are five-member marriages, and the only one on SOL is aroslav's Model Student. (Jacob Hopkins didn't quite pull this off, though it tried harder than most stories with harems that large. Daze in the Valley fell down hard at this, despite the fun.)
(This is one area where Chinese webnovels have a slight advantage: the historical upper-class practice of a man having a senior wife plus concubines is a ready-made model for one way to structure a plural marriage. Japanese light novels/manga/anime tend to be just as hit-or-miss about it as Western erotica, unfortunately.)
So for those who read in the genre, is there a size limit for you? How large is too large? And what stories with ensemble relationships can you rec?