What you are looking for is the
Boglehead 3 Fund Portfolio. My personal take (and I would wait for
Blazin
or
Sanrith Descartes
to shit on it) is that 60/20/20 is not as good as it was 20 years ago because a few decades of near 0 interest rates have made bond funds less important and a the current climate of international holdings is centered on China and Europe which are going to have real issues with their economies in the next 20 years due to demographic decline. Personally, my boglehead 3 is 80% in
VTSAX, 10% in
VTIAX, and 10% in
VBTLX. The bond fund is going to look really bad compared to other indexes but that is because bonds are supposed to be there to sustain your portfolio when the stock market is bad and stocks have been stellar since rates have been held near 0. Who knows, as the rates rise and quant easing is eliminated again there may be a resurgence in the bond market.
I say all this as a relatively ignorant investor working off practical concepts, much like yourself.