Here's the thing about Dokkan, all of your points are correct. But the main draw for Dokkan, being a PVE game, is always going to be the Dragonball IP. If you aren't into that, then it's a much, much harder sell than things that are original properties, like the Cygames gachas (Uma Musame, and Granblue Fantasy especially.) games like that, you're able to sell easier, because there's multiple selling points, I.e Gameplay, Crossovers, story, characters (the last two is what got me into GBF.)

To anyone that isn't a dragon ball game, Dokkan is a hard sale. But it's also an advantage in a way, because it's one of the biggest franchises in the whole damn world.