The older the guy, the more precise his preferences. I find guys in their 40s to be quite vocal about preferences. I rarely have long nails, and even less frequently polish them. One of my guy friend went nuts for them and propositioned me. 10 years of normal friendship jeopardized by petal pink nails.
My boyfriend likes just normal length nails but once they get long enough that he wants prolonged back scratches, I cut them. Not to be nasty, but bedtime is bedtime, and I don't want to lay awake scratching his back even after he has fallen asleep. He wakes up again as soon as I stop.
Just find your own preference and style, and let the guys that dig that come to you. It's easier to maintain friendships, relationships, your schedule and your sanity when you are not over enhancing someone else's favourite aspect of you.