They're fun fights I think. I found the second one the most annoying personally, the mechanic where you have the hearts over your head and then the arena is flooded with AoEs and random hearts moving out from the middle has tripped me up a few times so far, I haven't intuitively found the safe path through it yet. Rest of it was good though!
I think I'll have to run through them again a couple of times just to get comfortable with everything but definitely enjoyed the tier, and the story is a bit of fun too.