Personally, I dose 4000-5000 IU D3+K2 in the darker seasons and that has been working well for me.
Vitamin B12 is water-soluble and therefore should not cause accumulation in healthy people.
Calcium, magnesium, sodium, and potassium in balanced amounts along with K and D maximize bone health. Alkali metals supplementation alone is rarely a good idea because of the often common transports and osmotic competitions.
In general, a multivitamin, b complex, and omega 3 in the form of canned fresh sardines or anchovies (fish oil capsules are typically low in actual 3 and high in 6) is probably enough for most people.
5-10 mg/day of extra zinc during the annual cold season is fine too.
Don't supplement with E without a specific medical need.
My beginning D3 levels were 39 ng/ml, so just under the ideal range of 40-60, and not really deficient. I have not tested recently, though I believe my numbers would be higher now. I also try to get at least 30 minutes of sun exposure over most of my body 3-4 times per week. Fortunately I live where I can get good sun exposure year-round. Point is, test your serum D3 level and do whatever you need to get into the desired range, and don't take more than that level of supplementation. I do believe that sun exposure is a better choice than supplements, if practicable.
I'm entirely untrained, but my amateur evaluation of the situation leads me to take 50,000 IU orally once each week or two. I imagine that twice that amount would be fine, too.
That's not really science.
Given it's your body, the most valuable thing you have, perhaps a more fact-based approach is warranted?