Would it be good to just invest in VTI and EFA ETF's for 10 or 20 years?

Opinion

Depends on what kind of returns you are looking for, how safe you want to be and some other factors.. If you have 10 or 20 years I would be a little more risky, especially in a market such as this. As Warren Buffet said "Be fearful when others are greedy, and greedy when others are fearful." Read "The Intelligent Investor", great book."