Have been hearing that the consensus is this is supposed to be better than the first game, can someone who's played both share why? Thinking about picking this up some time down the line.
Others have already told you but I'd say that it essentially boils down to 4 major elements:
1-Improved mechanics: systems are expanded or refined, you'll have new battle system mechanics (latent powers, ex skills, night passives), more options with the job system (licensees), and more. All of that without making the game feel bloated or without creating systems the player doesn't have any incentive to engage with, which is great in my book. (btw some argue that the second game is too easy too break but your milage may vary)
2-Improved presentation: it's the best looking HD-2D game yet. Tons of unique animation work, asset variety, unique locales, stronger art direction than 1 (imo), beautiful set pieces/backdrops.
And, last but not least, what are arguably the biggest shakeups:
3-Reworked narrative structure: some chapters are split into sub chapters that you can tackle out of order, some chapters don't feature boss fights, other mid-bosses, others no dungeons, they aren't all "4 chapters for each traveler or bust" deals, and in general, without spoiling stuff, might feature surprises that the first game wouldn't throw at you. Ah yes, there are also crossed paths and a full-on finale.
4-Reworked world design: the map itself is not as "square", there's more diverse locales, dungeons (outside of the final chapter ones) are shorter, and together with towns now feature more verticality and traversal options thanks to ladders and canoes, sea exploration.
All of this stuff and more that I'm probably forgetting is (obviously) coupled with the strengths of the first game, which I imagine you're familiar with.