This game has a lot of questionable design elements, starting with the new monster card system. You can equip up to 3 of the 50 different cards for perks, and most of them are dropped by enemies. See where this is going? Castlevania gets away with this sort of "kill enemy; reenter screen; repeat 500 times until you get what you want" gameplay, because what you're getting is a cool new flaming sword or something; the cards are just perks, many of which are minor, like being able to climb ropes faster. Whee. There are some excellent cards, but most aren't dropped by monsters, so you're farming for HOURS for very minor "rewards". On top of that, dances are used in specific areas, but for half of them, there's no real hint as to where to use them, so you just use them on EVERY SCREEN. Oh, and they cost magic, too, so progress is slow and tedious, if you don't want to miss anything.
So, halfway through the third dungeon, I gave up and started over in Full Deck Mode, which starts you with all of the cards. Add two hours to my old playtime (38% completion) and I finished the whole game; cards were just wasting my time. I'd also forgotten to turn off hints, and you know what I got? Things to tell me where to use the dances and nothing else, so keep hints on, too. Game's great if you play the right mode.
Aside from that, mechanics are tight as ever, you've got all kinds of new skills and dances, and even some new magic. The world is an absolute joy to explore, with an engaging main world and very well-designed dungeons. They didn't get Jake Kaufman, but the soundtrack is still really good, and not far off the mark. Characters are the usual for a Shantae game, so fun and very lovable. I had an absolute blast with this one, once I got on the right track.