I definitely think there are some things they teach that do us good. You mentioned giving up smoking - that's got to be a good thing. Also, they do encourage people to be moral, not to over-indulge in alcohol, don't do drugs etc - it's just a shame that a lot of JWs ignore the advice. Bad language is another thing - I hate bad language and JWs do teach that you should not swear etc. I know a lot of people don't follow this though.
The trouble is, what the WTS teaches and what it does are often two different things. They say that we should follow Christ and develop a Christ-like personality which is excellent advice. But Christ was kind and loving and forgiving and went out of his way to help people. He didn't burden people with petty laws or make them feel worthless. I don't see anything loving about the WTS and their shunning policy. Also, they are pretty cowardly when it comes to exposing child abuse in their ranks. It's no good preaching that these things are wrong if you condone it by your actions - or rather inactions.
It all sounded so lovely in the beginning when I first became a JW. One day we would see a peaceful world without war, full of loving people who respect each other and want to do what's right. The chance to see your dead loved ones again. A spiritual paradise now where brothers and sisters will always be there for you. The reality was pain and rejection. The JW love is conditional love and I can do without it.
Terri