Just curious, what kind of conservative portfolios are you investing in? I was recently trying to get my wife and I invested in something similar, but didn't find many products. We are very risk adverse and recently (after maxing out 401ks) have been "hoarding" saved money in our bank, which doesn't help much.
The key thing for me was to constantly and continually invest. I'm sure you've heard the saying to "maximize time in market; don't time the market." I buy a mix of bonds and stocks that pay dividends. I'll skip reading the financial news from time to time and buy shares in low-cost funds when I'm busy or just feeling lazy.