So your mead will finish at about 13.3%. I have no idea about your yeast and nutrient regimen which is a huge part of making a good mead. I'll touch on a few items from your post.
Tannins - generally speaking I use FT tannins from the start. You can use them later though you generally need to give them enough time to do their work before you bottle. When used in primary they can help your mead clear faster.
Racking - For the most part you will usually wait until you hit 1.000 or lower on the hydrometer to know that it is finished. With the EC-1118, you should hit that point. Your mead will finish dry, but depending on the honey, it may have some residual sweetness to the tongue. On the first racking I will use the cap on my auto siphon to minimize how much sediment I pick up. Generally you can work the auto siphon down slowly so that you only put it near/to the bottom until that last little bit to minimize the sediment you suck up.
Back Sweetening- This is a personal choice. You might end up with enough residual sweetness for your tastes. You will use Potassium Sorbate at least 24 hours before back sweetening if you are using a fermentable sugar. If using something that doesn't ferment, then you can skip it. If you use the Potassium Sorbate, you should consider using Potassium Metabisulfite as mandatory. It is mandatory as Sorbate by itself can be used by some bacteria that will add flavors that you do not want, The Metabisulfite will inhibit those little critters and it is added at the same time as the Sorbate.
Oaking - Personal choice, but I will suggest avoiding chips and use cubes, staves or Xoakers. I do this before I back sweeten as it helps me inform my choice of sweetness.
Acid - I usually do these last but at least these taste changes are noticed immediately.