I'll dump my opinion now that I've played for a few hours.
Pretty much all the depth is gone, the dice minigame sucks (cosmetics is ok, if they had replaced the PR minigame with that would have been great), I don't understand a bunch of how the new scoring mechanics work. Writing seems fine.
The new rhythm gameplay is nice, though the strategy is gone from that as well, unfortunately. I think it's a little too easy on pro (but I'm a 10th Dan IIDX player so I think most games are easy), I've heard you need to finish a characters story to unlock master so no comment on that right now.
For all my negativity, I'm really enjoying it. We've gone from the very high stress IMAS 2 to the more forgiving OFA to PS, which is virtually a zero stress game. It was a great way to unwind after a shitty day at work today, because sometimes you just want to relax with a game.
IM@S2 felt less stressful imo. Easier than the rhythm gameplay in Platinum Stars imo. (I probably won't be putting it onto pro ever. Probably... >.>)
I'm still enjoying it but unlike IM@S2, I probably wouldn't play this while tired
we're in agreement on the dice mini-game though, it really sucks.