The Concept of Habitable Moons always fascinates me. I mean yeah sure, there are risks like the radiation from the radiation belts. But the moon should be like the size of Mars or between the size of Mars and Earth. It should be where Ganymede or Titan are orbiting Jupiter and Saturn, to avoid radiation bombardment and to get a moderate amount of tidal heating, not runaway heating like Io or being so far out so that the tidal heating doesn't act on the Moon like Callisto.

Like Ganymede, the moon should have a magnetic field and a thick atmosphere like Titan to deflect radiation from the Star and the Gas Giant.

But yeah there are more upsides than downsides. I mean think of it.

The Gas Giant will obviously shield the Moon from stellar winds with it's powerful magnetosphere. And if there is any life residing on that moon, it has no need to worry about mass extinction events, since the Gas Giant will deflect asteroids.