Play the way you enjoy the game the most. Seems a bit silly to ask other players how you should enjoy the game.

Personally, I think it's a bit strange to skip all side content until the end. Once you've finished the story, there's no real benefit to doing those side quests (don't need exp, side content is obsolete). Most players will say use side quests to level a second job, so, why not level both at the same time? Give yourself some options going through the story, or just some variety.
I also feel it's a bit silly to start crafting/gathering after clearing story, since you've skipped all the things crafting may have been useful for. Your only crafting goal at that point is to level it for the sake of having a leveled DoH/L, instead of having the option to keep yourself in the best gear as you progress.

So, for me, I feel it makes the most sense to level everything at the same time. Keeps everything similarly relevant, at the cost of progressing much more slowly. I don't mind the slow pace, and I get to enjoy the world a little more fully.