Hohoho looks great! I'm playing it on normal, my wife enjoys it too but to make things easier for her to see the story faster I did choose that difficulty. New Game+ brings many extras?
This game's really addicting right? At first I confess I though it would suck because of its Idol-ish theme, I'm kinda "blabla I play SMT since Super Famicom blabla" so I got angry when I saw an SMT spin-off with that style on Nintendo Directs. But, looking around, persona 4 had that (specially that dancing all night game), it's like a tendency right? I've been in Japan last year, Akihabara was full of idol games, manga and anime, so the public is going to that direction I did stop to get grumpy.
I personally love idol culture and I have the SE of Persona 4 Dancing All Night ww
To be entirely honest, it plays a lot more like a Persona game with elements of of MegaTen and FE mixed in to the fray. Being a long time ATLUS and JRPG fan I enjoy it a lot. The battle system is the best part, and that is what is the most important, right? Grinding doesn't really feel like grinding. New Game+ allows everything to carry over and there are some new quests that have extremely hard bosses, "ultimate" weapons for each character that are not available the first time around, and a harder difficulty for the Arena. Arena is just fight 15 battles in a row with no stops, can't change characters or use items and you get rewards. Lunatic is unlocked after the first play through and nothing is carried over except your monster encyclopedia.
If you want the true experience, while I do own the original, I dumped my copy to my PC using DDD and downloaded the patch which removes all the censorship and changes a lot of the dialogue (specifically chapter 2 had over 300 lines of dialogue changed and re-recorded by the original cast to match the English "localization") and I play it through the Wii U Homebrew off an SD card. If you're in to that kind of thing it doesn't require a lot of effort or mess up your Wii U at all.
All the info can be found on GBATemp under the Tokyo Mirage Sessions #FE Reincarnation thread.
Idol Culture has been prominent in Japanese media for so long there is no use in fighting it, even back as far as 2010 I can remember AKB48 and MomoKuro taking over. Although their popularity is dying all the new groups are continuing the trend.