When I was a teen I sort of idolized pettite woman with medium sized breasts and nice legs(oh and feet).
As for what a girl looks for I wouldn't care, I'd probably look her straight in the eyes and whisper softly into her ears: "I may look frail and not built like a freight train, but I have huge muscles. Trust me. My brain muscle bulges at the seams, my heart pumps as strong as a hot tub filter and my love muscle can lift a mountain..... dew".
And based on personal observation. Muscles are totally out. It's all about being skinny these days. And I mean sickly skinny, lanky, chickenleg, tight, tapered jeans borrowed from the deepest confines of your sisters closet. Hair in the face. And an obscure band shirt buzzing around sum scummy hipster faux irish bar. I see a guys when I'm out and I'm like "I bet if I punched you in the sternum you would die." but apparently that's HAWT!