I would suggest having simple templated AA (asset allocations) by age setup with this to both educate and make it easier for people to invest. Asset allocation is one of the most important concepts in investing. Simplicity is also key - a 3 index fund portfolio is sufficient for most people. This is similar to how many Target date mutual funds are already setup.
For example:
Age 18-30 Template
70% domestic equities (Total US Market Index Fund)
20% international equities (Total International Index Fund)
10% bonds (Total US Bond Index Fund)
Age 30-40 Template
60% domestic equities (Total US Market Index Fund)
20% international equities (Total International Index Fund)
20% bonds (Total US Bond Index Fund)
Age 40-50 Template
50% domestic equities (Total US Market Index Fund)
20% international equities (Total International Index Fund)
30% bonds (Total US Bond Index Fund)
Age 50-60 Template
40% domestic equities (Total US Market Index Fund)
20% international equities (Total International Index Fund)
40% bonds (Total US Bond Index Fund)
Age 60+ Template
30% domestic equities (Total US Market Index Fund)
20% international equities (Total International Index Fund)
50% bonds (Total US Bond Index Fund)