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.