By using the T2 durability buff set, you should be able to pristine 90-99% of your combines.
Without them it is a crap shoot!
But my big question is where are you trying to grind to? lvl 50? lvl 30? lvl 20?
At lvl 13 you are just reaching the point where you can make money from your labor. Why rush through it. When those T2 combines turn gray, you won't want to make them any longer and so you won't be seeing profit from them.
My suggestion is to organize your workflow and enjoy the process.
I tend to set aside the first crafting session of the week to make WORTs. During my next session, I make my sub combines and during the third, I make the finals. This way, I have lots of fresh product for the weekend when sales are brisk!
Start by putting a full set of armor out for sale and seeing how fast it sells. If that works out, you can expand to 2 full sets. Or one chain and one plate... or 2 and 1... or 2 and 2...
T2, both plate & chain should sell well since players have chosen their class and outgrown their original questsd armor but cannot begin the AQ series for another 5 or 10 levels.
When I was tailoring in T2, I was cranking out 3-4 full sets of cloth and 3-4 full sets of leather each week... and making BANK!!!
Savor the moment, my friend! Be a merchant! (Doesn't mean you can't adventure too!)