Hmmm, I don't think I really have a type, but I'll look at the girls I've had things for and look for common features. So let's work top-down.
Hair - An even split between dark brown and dirty-blonde hair, which I think is pretty interesting. Dark brown hair is probably my favourite, makes me just want to stroke it. Straight hair doesn't do it for me, and nor does bottle-blonde.
Eyes - A very even split between blue, green and brown. Doesn't really make a big difference to me, and isn't something I hugely notice; even though I like looking into someone's eyes, the actual colour is beside the point.
Mouth - None of them have particularly huge lips, but all of them have infectious smiles (except one, who rarely smiles at all any more (definitely not my fault, I swear)).
Breasts - A man (even a gay one) who says he doesn't like boobs is probably lying. The majority of the girls on my list have larger than average breasts, but I wouldn't say it's a deciding factor at all, to be honest. It more fits in with...
Waist & Belly - Apart from one, who would best be described as willowy, the girls on my list aren't especially thin. They aren't what you'd call fat at all either, and if I was asked to describe, I'd probably say soft & warm to hug. Certainly, a perfectly flat stomach is some way off my list of must-haves.
Derriere - Bum-wise, there's a bit of a range, but Kardashian-style behinds generally aren't all that great in real life, but you're pretty hard to find a bum that looks bad in jeans.
Legs - Stick-thin legs are a huge no-no for me. Soft thighs score good points.
Height - A pretty wide range, from some who are over a foot shorter than me to some who are somewhere near an eye-level. I'm tall enough for both of us, really.
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Okay, so that seems to create a picture of an ideal girl with long, wavy brown hair, brown eyes, and a fairly curvy figure, who smiles warmly and gives great hugs. For bonus points, she could be wearing a knitted sweater and a loose skirt (which is a slightly odd combo, but hey, bonus points). Well over half of their names also begin with the same letter, oddly enough. I'd say that's pretty accurate, tbh (and pretty long).
I'd also agree with the earlier commenter that confident posture is also very attractive.