First off, this is how you should define nice:
Considerate towards a woman
Faithful in word and deed
Thoughtful
Not letting someone walk over you in regards to money, time, what is important to you etc. -- this is a genuine life skill. You have interests, make sure she knows it up front and it's all good
Good women appreciate this.
Advice to the youngins here: for all of you unhappy about the women who don't appreciate nice guys, you should be happy if they put you down early, even if it hurt. Because they either have some bullshyt personality, bullshyt habits, or fukkin with low lifes. Her p*ssy ain't worth it. Either way, keep moving and you will eventually find a woman that appreciates you (hint: maybe she is the introverted and quiet type like yourself).
The only people bytchin about women who don't like 'nice guys' are they dudes stuck on one or two women they borderline worship and are frustrated that can't get any play. Throw them to the bushes. Get out more, seriously. If you put that much advantage in a woman's hand to make her think you can be her backup plan/doormat, I have little sympathy. I was once in this position until I enlightened myself and met my future wife six months later. Move one - there are more Black women than men in all varieties. I am tired of the p*ssy excuses.