FFXIV is a very pretty game. As noted, its role models are typically upstanding members of their communities, and you are "good". There will be violence, but it's all very sparkly and I didn't think it was too bad.
The game is relatively easy to play, but much levelling up will come from playing with others in daily dungeons and mini-dungeons, so if your child is under 18 or so, you may want to monitor them - or play along yourself!
There is a repetitive, slow crafting process, but it can be quite relaxing. It's very well put together, in that all crafting professions cross each other - you'll need something from one to help level up another more expertly, for example. It might, however, cause some kids to spend too much time online, so again, this should be monitored so it doesn't become addictive.
The outfits can be somewhat risque, particularly for female characters, as with most MMOs. You should also be aware of the perceived differences between genders, and although it's not hugely prevalent, keep an eye on things such as "Little Ladies' Day", which is meant to celebrate young adult women. It comes across as a little backwards as a result of this, and a light talk with your child beforehand regarding sexism in gaming may be required.
There is a store to buy non-game changing items (such as costumes and jewellery) . It is also a subscription-based game.