Finished it today, just over 73 hours. It took a little for me to get into it, but I ended up really enjoying it. If there's one criticism I have, it's the scaling of both enemies and teammates and overall difficulty is all over the place. If you do even a little bit of grinding (I'm talking <1 hr, not even that crazy), you end up way over-levelled, new party members join under-levelled, and then you end up overpowered for the enemies for a large part of the game, till you reach act 3, and you can hit beyond 9999, then suddenly normal enemies feel like bosses with the inflated health they have till you catch up. But then the final battle not scaling with you also makes it really anti-climactic. It becomes laughably trivial. I enabled the damage cap again, and just kept skipping turns to make sure I at least caught some dialogue, otherwise I would've one-shot them.
Also I did overall enjoy the battle system; the customisation reminded me of FFVII materia a bit the way you can mix-and-match everyone, but when you come across a Lumina combination that makes you OP, boy are you OP! Even with a non-optimal build and some sloppy play, I found something that let me beat Simon in maybe 10-15mins, after a number of retries and some luck.
But it's probably in the top 5 of RPGs for me. Chrono Trigger, FFVII, FFIX...I'd be happy to slot this in the no.4 position for me.