This is mainly a FF focused comment. I might come back later and ramble about other franchises though.
A lot of JRPG franchises generally only have themes in common. So you can play Final Fantasy 6, 7, 10, 11 or 15 and have a self contained story. I donno if it’s been confirmed by Square but I do subscribe to the theory that Final Fantasy Tactics and 12 take place on the same continent, just a few hundred years apart. But even then, both titles are standalone and have nothing in common other than the same Ivalice.
There are a few franchises that have continuity like Breath of Fire(iirc) and XenoSaga.
As for where to start with Final Fantasy, 6 is a really good standout retro one, 7 is always a favorite, and so is 10. I don’t think you can go wrong with any of those. If you really like politics in games, 12 has all that and more. It’s my favorite of the bunch but that makes me an outlier. I also don’t recommend starting with it because it’s a huge deviation from the main game mechanics.
idk why I deleted that comment, but also learned that you can undelete lol.
I’m not at all sure about the timeline order so that’s pretty cool. For some reason to me FF12 feels more future-y tho. I do recall someone stitched the map for the original Tactics and FF12 and they match up pretty much exactly.
Do you have more info on the “child’s dream” take? I’m curious.