That was what I'd assumed; anything with a really skewed gender ratio is pretty much giving warning that it's either a harem, girls' love, or boys' love.
I figured the default was predominately male. The only females being potential love interests and/or thrown under the bus when plot and male character advancement.
For Western media, that is true, but the sheer predominance of female cast members in anime is different. These are the shows I'm watching from October (I don't recommend checking most of these out. Dodge the bullets I didn't):
Tokyo Ravens: 1 main guy, about 4 main girls, +male "sidekick"
Log Horizon: large cast, evenly split male/female
Kuroko no Basket 2nd Season: sports anime, so mostly guys
Nagi no Asukara: gender symmetry
Magi: The Kingdom of Magic: kind mixed, lots of characters probably 2/3 male, but quite a few named female characters who get their own backstories.
Yowamushi Pedal :sports anime, so mostly guys
Diamond no Ace :sports anime, so mostly guys
Gundam Build Fighters: mainly male, but it's pretty much a sports anime
Golden Time: romance anime, even split male/female
Strike the Blood : 1 main dude, almost everyone else is a girl
Kill la Kill : both MC and antagonist are women
Samurai Flamenco : slight bias to guys, but still has ~5 named female characters
Those are the 2-cour (25+ episode) shows i started watching in october. Pretty much the only ones with a predominance of male characters are the ones which revolve around men's team sports. every other genre including magic, battles, romance is either 50/50 or predominantly female characters. Note for the "harem" label: Tokyo Ravens and Strike The Blood are both pretty similar to A Certain Magical Index. So if you consider Index a harem, then those are harems, too.