Honestly, it feels like CSII expected you to watch those events, lol. What with Rean's incessant need to bring back his true love. When I went back to CS after finishing CSII, it really helped in making sense of Rean's whole motivation. Still comes out as sort of kinda-clingy-insane, because he has his own issues to work out, but that's whole other topic, lol.
When I first read about that delay set-up, I was like "no way, some of these bosses have a resistance of 15 Delay". Tried it out, holy shit. It's actually pretty consistent! Regardless, I was all about the Tauros + Domination + S-Craft life, lmao. There's no reason not to load up on gems and SR quartz, I think the only normal quartz that's worthwhile using is probably Action 3 and Cast 2.