The Galaxy class was a flawed design, as shown by how easily it almost blew up multiple times, thanks to its extremely sensitive warp core, warp plasma system, and warp engines. However, by DS9 the flaws seem to have been worked out, as we only ever see the U.S.S. Odyssey blown up.
After that, Galaxy-class ships are used as battleships and we never see one blown up ever again. Additionally, every Starfleet ship we see destroyed gets mission killed, rather than having a warp core breach. Miranda-class ships died in droves, but were always left with gaping hulls, rather than being vaporized. Over all, that fits better with the remains of Wolf 359, further showing sensitive warp drives are something isolated to the Galaxy-class.
That being said, the Galaxy-class was a good ship concept. It allows for crews with families to live in a town like setting for years on end, without the need for returning home. Even a ship full of single people wouldn't be able to maintain a mission years on end without any hope of leaving, but the vast amount of people, especially those not required to follow the informal military structure, mitigates the issue with variety.
The ship does face danger, but the story of Star Trek is danger can arrive anywhere and kill millions without a sound. Facing it head on might be even more dangerous, but everyone there knows what they're getting into, and by knowingly searching for the unknown they can be more ready than someone assuming their safe on a planet.
Regardless, Picard never liked having families, let alone children, on his ship. Part of that was because he didn't like children, some because he didn't like them or anyone outside the actual crew being in danger. It probably would be better not having families on board, but like I wrote above, the mission duration would have to be a year at most.
Did we see any ships other than Defiant class and the Enterprise E fire Quantum Torpedoes?
The U.S.S. Lakota is stated as having quantum torpedoes. It underwent significant upgrades before fighting the U.S.S. Defiant in DS9: "Homefront." Neither crew wanted to kill the other so they were both pulling punches, but the over all impression is both ships are equal. Quantum torpedoes get stated as something which, if used, would win the battle for either ship.