I've heard from many actors at many conventions that the set was a lot of fun. They often said tey ruined a lot of takes by laughing. They played a lot of pranks on each other and joked around a lot. There are a few famous stories, one people refer to as the pon farr story. I heard Garret Wang tell it and it was fun
in fact when DS9 actors are asked about life on the set, they say it was very serious for them "we weren't like the Voyager crew, we didn't goof around and have a lot of fun" Several DS9 actors have said that
and you know what.....so what if it wasn't super fun on the set. They're not really there to goof off. My job isn't super fun either
This is exactly what Aron Eisenberg said at Galaxy Ball 2001. He played Nog on DS9 and the young Kazon in a VOY episode. He's aid DS9's set was, if not tense, then serious, while VOY's set was fun.
The fact that the men of VOY try to get together once a month shows there weren't a lot of hard feelings on the part of many of them. In fact, it tends to show that they were friends as much as co-workers, which is not that common. But it was, in many ways, "just a job" like many of the other acting jobs these people get.