I understand the blacklist issue, but perhaps there's a way to have a name remain on a blacklist despite it's change.
This already happens when names get changed. peoples friend and blaclists change to the new name. BUt if you don't pay much attention to your blackilst, you may still not notice.

Like I said, I'm generally against making important thingsl ike this changable. It gives weight to the decision and makes people put more thought into it. Allowing name changes will just lead to an increase in joke/silly names that people pick because they know they can change it later.

But I also realize im in the minority on this and most people don't like or can't handle decisions. In real life, changing something about you physically or changing your name is a big deal, and you can't just do it on a whim, such should be the case here. Any name change service or sale of fantasia should come with a significant price and a time restriction.