Don't care. Though clean and smells good is key, as you said.
Curly might not be everyone's favorite, but it can certainly be just as attractive, and it is NOT gross. (well, you could make it gross, just like you could make straight hair gross. But it isn't gross because its curly)
I do like "wavy" more than straight or tightly curled. But like I said, a pretty girl, especially a NICE pretty girl, can have any hair type; most guys don't care. Even if they have a preference. Meaning your guy MIGHT say he prefers "straight, brunette" hair but you know he likes the look of Scarlett Johansson's "wavy blonde" too. At least, he would NOT complain about it if that's how you looked :-)
I have naturally curly/wavy hair and my boyfriend loves it because one day it'll be exotic and wavy and the next day it'll be smooth, silky, and straight. And I think everyone's hair SHOULD smell good, it's like an unwritten law lol