Not sure if I'm doing this right

[Xenosan]

You should try your hand at sachetorte fo sho, bacon broth too. but 2,3,4 star synths aren't always going to be your money makers, you could be making gil from any of your crafting classes.

My approach is not to fall into a niche. Some of my consistent sellers are categories/items I would not have guessed and had just attempted as tests. But I don't think you want to move yourself into that corner where you're only relying on one item or category.

I use the favorites feature in the craft menu specifically for the purpose of selecting items I haven't tried synth > selling with yet, and change it up a lot.

imo if you wanna see an increase it would be getting your miner and fisher to 50 too, the fishing 50 would let you have a fishing retainer for those harder mats (esp if you wanna cook, going to be at a disadvantage to the competition if you don't have at least 1 fishing retainer), and the miner will let you craft in Mor Dhona, gathering clusters every 4 ingame hours