That are a lot of things you can craft but it comes does to one simple thing, is the item worth more then the materials would sell for. Let’s use Lev 55 Augments as an example, we buy the materials for 100k.
To make a profit, we need to list it for 107k on the GTN. Greedy Hutts will take a 6% cut for selling on the GTN, and spamming the fleet takes too much time (unless it's an in demand items like when Lev 55 Augments first came) so we have to factor in the 6% cut. Selling the Augments for 1k is not much profit so we have 2 more things to factor in, can you get Critical result (Crit = get a free one) or not.
If the item can get a Crit , then you can profit from selling the free ones. For a 100k item, I like to sell about 5+ a day to be worth my time. Hopefully for every 5 you make, you get free one. In this example I was selling cheaper then current market price to push fast, but still make as long as we can sell for 107k then we will profit when a free one is earned. For items that sell for 500k to 1 Million item, a Chance to get a free mill every 1-2 days is not bad. Always try and get the materials cheaper, buying ahead of for the next week.
If the item can not get a Crit result, I like to factor in about 25-50% of the cost to make it. In our example of 100k, that would be 125k +. Next can you sell the item for you that price? If yes, then start getting ready to pull in the credits. If not, try working on getting the materials cheaper. Sometimes prices can be cheaper on weekends, start of the week. Check everyday you can.