ETF's and portfolio construction

Portfolio construction for retail investors is oftened made out to be far more difficult and technical than it really needs to be.

I don't claim to be an expert on the subject by the stretch of anyones imagination - but I have got some thoughts around using ETF's that might be interesting for active South African retail investors trying to level out some of the volatility in their portfolio.

ETF's in my portfolio are (in my opinion) great for one reason - variety....
- Access to asset classes that are not normally open to retail investors (e.g. bonds)
- Access to markets that are not normally available to retail investors (Japan, US, World indices)

These are the ETF's that I've tried to blend into my portfolio:

DBXJP - Deutsche Bank Japan X-tracker
DBXWD - Deutsche Bank MSCI World Index
DBXUS - Deutsche Bank MSCI US Index
ZGOVI - Investec's government bond ETF

On top of that I'll add in the RMB / Bips Inflation-X product when it lists later this month.

My strategy at the moment is to mix in about 20% of these into my portfolio just to try and balance out the stock-picking and asset diversification.

It is a pretty cheap and easy way to balance out this risk - Anyone else using these tools for the same reason?