Goku - Yeah. He's more or less a "happy-go-lucky" kind of character in general.
Vegeta - To some extent. While he still thought about competing with Goku by the end of Z, there didn't seem to be any negative energy about it. He also appreciated his family.
Gohan - As an adult, yes. Out of all the Z Fighters (perhaps besides Krillin and Yamcha), peaceful times are something that Gohan would benefit from the most because of his lifestyle.
Piccolo - For the most part. He had his bond with Gohan, and fusing with Kami made him more tranquil.
Tien - He doesn't appear much in the late portion of the series, but based on his interaction with Gohan (during the Buutenks fight), he seemed fine. The series makes it clear that he knows his limits (e.g. declining the offer to train in the RoSaT, and acknowledging a large gap between his power and whoever the top dog is in pretty much every saga), it's mostly a matter of Tien not really having a passion for anything that doesn't involve martial arts.
Krillin - Like Gohan, he's one of the Z Fighters that appreciates a regular life. He was never really obsessed with fighting or being the best anyway.
Yamcha - Same as Krillin, basically.
Chiaotzu - He seemed happy whenever he was with Tien, and spends most of his time with him.
Cyborgs - #17 became a Park Ranger and Super portrays him as being quite passionate about it. He also had a family of his own. As for #18, she ought to be content with Krillin and Marron.