As for older ones, while I don’t mind retro games, they feel a bit too retro. How would you say those older games are, if you don’t have any nostalgia for it?

I'd say 5 and 6 are worth playing even without the nostalgia factor. The job system in 5 is really fun to play with and the plot is solid, and 6 is one of the classics everyone should play once.

As for the earlier games, they are surprisingly decent despite their age but I'd say they are best played as a history lesson to the genre.

6 is my favorite of the entire series so I might be too partial to it, but I do really feel like 6 is the their first big step into a somewhat modern/more mature storytelling. 4 also has a good story, but it’s still kinda tied into this idea of the main characters dealing with crystals and whatnot, and that never really resonated with me that much.

6, on the other hand, has a narrative beyond that. You don’t worry about silly crystals at all, and instead of some vague evil plaguing the world because the crystals got broken or out of alignment or whatever, you have real threats from a nation that’s using magitek technology, then later on even worse threats (and the best main antagonist of the series). I also think 6 has the most interesting characters, and even though there are a lot, almost all of them have interesting back stories you can explore. And many of those stories are tragic. You may have heard about suplexing the ghost train, but the story around the ghost train is heartbreaking. This is the first of the series where I cared about all these characters because they are written well.

It’s just a game that feels whole. Things that happen feel correct for the setting they have set up. 6 and Chrono Trigger are the absolute apex of 2D RPGs before the world jumped to 3D. And another big plus is that these games still look gorgeous because the sprites never get old unlike the boxy, ugly humanoid figures of 7.

As for the others, 1-5. They are alright. 4 is the most important of that group. It’s got a good story, though it’s not my favorite. I think the Pixel Remaster versions are pretty nice because you can set the xp gains to 4x, cutting out a TON of grinding in the older ones. And you can turn off random battles if you just want to get through a dungeon. I’ve played 2, 3, and now 5 this way. I think it’s neat to see how the series has evolved, but if you aren’t too worried about playing them yourself you could surely get by by watching some video synopses online. That said, with the 4x bump, I got through 2 and 3 each in about 10 hours. So not bad at all.