Here is an interesting graphic 'Periodic table of Vitamins': http://www.kombuchakamp.com/wp/wp-content/uploads/2011/05/periodic-table-of-vitamins.png
Do we need supplements? I am of the opinion that because of agricultural practices depleting the soil that supplementation may be needed, even if eating paleo. We use supplements but I am trying a staggered routine, so not the same supps everyday and on weekends we do not take supps at all.
I'm with you as an advocate for supplementation when taking in to consideration the condition of our soils and the feed we supply for animals that we eat. In my opinion it is a good idea to supplement so long as that is what you are using it for....as a "supplement" to an already balanced quality diet. Not to try to create sufficiency from a crappy diet. After getting your ducks in a row with food, my daily recommendations include: -an quality EPA/DHA supplement (fish oil, krill, or at least a decent alga DHA) -probiotics (6-9 strain probiotic culture of at least 2 billion of each) -vitamin D in the months of no sun exposure -and from time to time to cover your bases, a whole food and/or multivitamin supplement Also I consider on occasion for special few, digestive enzymes, extra anti-oxidant, Mg/Zn, but these I don't recommend for everyone and not everyday
Why not eat a variety of dif nutrients every day instead? I "hunt" the freezer daily for a dif meat. Sometimes we cull a deer, buffalo, caribou, moose, elk, or boar. I manage to pull up a beautiful Alaskan salmon out of these PA waters at least 3x a week. A few times a month, I manage to arrow a pastured chicken or wild turkey. I "forage" every day for a few dif FRESH, organic vegetables when were not growing our own. We eat offal a few times a week. We make bone broth. We make organic sauerkraut. I have never been vaccinated. I haven't even had a cold in 20 years. Ya know what I don't do? Supplement.