What you are saying makes sense. How do I determine what mix I need to take?
What I did for myself was lay out a foundation. Asked my doc for a recommendation for a good multi-vitamin/mineral supplement. Then I added a high quality Omega oil supplement. These oils are so important! I had so much trouble with hypoglycemia until I started taking oils 3 times a day... now I don't have to snack between meals because my blood sugar is stable. Next is Vitamin C (The cheapest way to take C is using the crystals that dissolve in water or juice. The taste is tart and tangy.) That's my base. If I were limited to just three, those would be the ones I would pick.
Most multis don't contain enough calcium and magnesium, so I add extra... these are vital for detoxification. They work together best in a 2:1 ratio, ie, 1000 mg calcium, 500 mg magnesium. You can find them packaged together. I have read that the citrate is supposed to be easiest for the body to assimilate, but don't know if that's true..
Then I add antioxidants such as D3, E and B-complex and I supplement with additional B-12 in a sublingual.
After that I add the exotics on an as-needed basis. Stuff like aminos, anti-inflammatories... people who take statins should take a Co Q-10 supplement. Stuff like that. You could go on and on until you're taking enough vitamins to choke a mule.