When I was younger I was very up-front about everything, to the point of being almost cruel with the truth. I do not lie, and I don't tolerate liars or thieves so I made it a point to call out such behavior.
Now I am a bit older and I still do not lie or steal, and I expect others to do the same. However I tend to be more diplomatic with my words, I choose my battles more carefully. I make a note of untrustworthy types and only associate with them if necessary, the friends I have are of excellent quality. I can trust them with my life or my families life. I reserve my emotions (for the most part) for my friends and family, and do not show all my
cards to everyone.
As for playing well with others, I try and be courteous to everyone. Even the people I do not agree with. I like to tell people I have a mental list, everyone starts at zero on that list and its up to you to go in the positive direction or negative.
I know that if everyone gives more than half in a relationship it will succeed.