I really do like Goten and Trunks as characters. They add a lot of needed fun back to Dragon Ball.
Goten even gets a hobby, as we see him finding a bug in a previous chapter and holding a bug-catching net in this one. That's more than we know about many of the older characters.
Trunks is also a great addition to Vegeta's character. At this point, we can finally see Vegeta stop acting as a selfish villain all the time. He actually takes his son to the amusement park (or says he will), which I would say is probably the first good thing we see him do in the series.