I would avoid doctoring too much, but that is me. No problem in tossing in some tannin, etc. But I would leave out the pectin, and acid blend. The cider will clear fairly well on its own and it is more authentic. Don't put in acid blend.... use malic acid. Apples do not have any acid in them except for malic, Acid blend as three types.
be a scientist about your apple hooch - you can't go by 5 lbs sugar, a tsp this a tsp that. You need to measure your sugar values (O.G.) and check your PH if you want to replicate it. As a beginner it is probably better to leave the PH alone until bottle conditioning (unless the PH is 4.0 or above). If you want a wine styling go for 1.010, if you what a cider styling go for 1.067 ish. My advice would be to ferment dry and back sweeten as needed. There are some great books out there, and a lot of science to marry with the art. Let me know if you want some books to check out.
Build your cider from the ground up (press it) and you will see a huge difference.