What should I prepare for the future?

I'm thinking about skill-ups, but also about next season, the season after that, and even further ahead. For example, should I keep upgrading 'True Words' to rainbow rarity, save up secret dungeons, or when should I seriously start focusing on optimizing enchantments? Any advice, information, or tips would be greatly appreciated (*^^*) Even when I look at the speculations and analyses of 'Sages' on official accounts like Discord, I only have experience up to 4th job classes, so I don't understand what they're talking about (￣▽￣;) I'm writing this post hoping for your comments. Thank you in advance ┏○ﾍﾟｺｯ