Having lived in Korea for 5 years, I learned a lot of different recipes and traditional ways of making Kim chi, from the oldest of ladies. I never would cook with the younger women, they are awful moms and grandmoms are the best. However, I did spend a few months with a very nice old farmer couple.
My only suggestion is not to shred the cabbage or the radish. You also might want to try green onion/or scallions instead of diced onion. The green tops add a lot of flavor.
Nappa or Chinese Cabbage is a preferred choice. The best way is to wash them about 2-3 medium sized heads, and cut any dirt out but leave the cabbage whole. Then slicing the tops lengthwise into 4 sections all the way but leaving the bottom attached. Then salt it and the radish with sea salt as you suggest but we use a large handful. Let it set until it is wet and soft( I usually put a large plate covering the cabbages and put a milk jug ontop to keep them submerged, but traditionally they add the salt dry and let it sit. After about an hour or 2 the cabbage is soft and pliable. I rinse it in fresh water because I like to reduce my salt levels. Then drain. It shouldn't be dry but not fully saturated either.
Then make a paste using dried chilis. I wouldn't suggest cayene, it is too sharp, a more rounded flavored chili would be closer to the Korean chili kochu. It is actually very bland but adds a lot of heat later on. Never burns the tongue but clears out the nose.
take freshly ground up dried chilis, ginger (we usually use 1" cube shredded, I don't know about spoons, about 5-8 garlic cloves crushed (three just isn't going to do it), and the green onions, sometimes we add a little sugar not much though less than one spoon. Take this and spread it between each leaf of the cabbage, use gloves. When mixed with the cabbage it will make a paste and keep rubbing it in until smooth. Do this to all cabbages. Place them in a plastic tub and let it sit room temp for a day. Then refrigerate it. Do not open the lid in the fridge or you will ruin everything in your fridge. The air ruins milk quickly. There is nothing worse than Kim Chi flavored milk.
I traveled to every province and went to the huge kim chi festival. I never saw anyone use apples. That seems very strange to me, but if you like it, I cannot judge. Never saw caraway either. Sesame is common, Juniper sounds interesting.
If you are going to make with carrots or other radishes, or even cucumbers. These are all different types of kim chi and the recipe and process is slightly different. Not common to mix cabbage with these ingredients though.
