I'm a ways into Chapter 2 at this point and it's just starting to really click for me. I love the exploration of Erebonia and the political structure of that empire. The pacing is a bit slow, but the characters are fun. Some of them are a bit school anime trope-y, but I trust the Kiseki people to flesh them out. Hopefully that happens sooner than later.
It took me an embarrassingly long time to realize how much they changed the Orbment system. I was trying to make lines and was super confused when new abilities weren't showing up on my characters menu. I didn't realize that arts are their own special quartz now. That's an interesting change, and cool for usability, but it definitely hurts a bit of the way the Orbment lines would make each character feel unique. I actually still am not sure what lines do anymore. I should read the tutorial again.
The master quartz idea is great.
I really don't have much of a clue what the lines are for anymore in the quartz section, but I think they're a good replacement for the orbment system as there are significantly more quartz in this game than in Sky, so you can basically class each character to be proficient with a certain kind of quartz as there's far too many to make everyone feel similar (unless you're giving them all the same kind of quartz, which is dumb).
As for the story, man it goes places. As an introduction game, the ambition of the story and cast in CS1 is off the charts compared to Sky FC. The pacing is arguably slower than FC's is, but the always amazing thing about Trails is that every new chapter is better than the last, and that holds up here more than ever. I won't go into more detail about story/character stuff since you're super early on and this isn't the place for it anyway.
And yeah, Master Quartz is a really cool idea.