The thread confuses two different [albeit seemingly similar] roles. Troi is a counselor and Guinan is not.
Troi is no doubt qualified, has numerous 'sessions' which we never see and is generally good at her job. She helps numerous people throughout the show to overcome certain tragedies in their lives.
Guinan is worldy. She is wise. She isn't just a bartender, she is a centuries old woman who has no doubt seen a lot of stuff. Your little love-life problem or ethical quandry is likey nothing she hasn't seen before. She has no qualifications but she is a damn good source of opinion and a useful measuring stick to keep you grounded and on track.
They provide a similar service but it IS different. You wouldn't walk into Troi's office and ask "How do I get girls to like me?" in a similar way you would not walk up the bar and say "My brother just died on Earth and my whole world has just fallen apart" while bursting into hysterical tears.
I think I agree with this. It's what I would have put into words if you hadn't done so.
Several of you mentioned the way Troi dressed. I don't think I could deal with her trying to help with with mental health issues while her chest was popping open right in front of my face. Seeing as to she could probably sense this in me, I'd probably just be honest with her about it, maybe something like "Look, you know that I'm physically attracted to you, so I don't feel you could help me because I'm just going to be too distracted with your physical appearance to concentrate on any mental issues I have".
The whole Barkley thing was idiotic. I only enjoyed his character once, in that episode where he takes them to the centre of the galaxy. The transporter episode (Realm of Fear?) was ok too. I lol'd when he kept asking the computer for more birds