some new and some the same.

The tutorial (where you play Riko) is pretty much a synopsis to the third layer. Once you start the real game and make your own character, its then a "What everyone else was doing while she was gone" kind of thing as you make your own way down.

The Hello Abyss mode is essentially just a tutorial and recap of the story from the start to Riko and Reg entering the third layer. The Deep in Abyss story is non-canon and is pretty decent honestly. It gives you a chance to get more lore on the world and characters and have more interactions with them.