an ever expanding field. (Not for me, it's too confusing; the plenitude of options resolves nothing).
ever expanding , absolutely , i got into VAS early in my investing adventure as insurance + growth potential
if i hadn't been looking for growth any of the top 200 index funds probably would have done the job in 2011 ( the market recovery since then did the real lifting , along with the DRP on quarterly divs )
i still prefer a LIC over an ETF when the decision is tight , i don't mind paying the extra fee for an active manager that gets results ( most of the time ) , but watch out for the ones that use Mickey Mouse benchmarks
however some ETFs offer exposure to difficult ( and niche ) areas , say where i do not want to buy ' the whole Asian market ' but just one nation or certain sectors in the local or global market
however this quirkiness comes at a cost both in liquidity ( less chance of an easy exit ) and higher fees , sometimes buying an Aussie major miner or bank , will do plenty for the laid-back investor ( as would say WES bought in 2015 or before .. or after if you didn't really like COL , WES went below $31.50 after the COL demerger )
research is very important in ETFs once an ETF is floated most of it is handled by computer so only MAJOR issues are handled by a human interaction ( like they had to change the internals of HVST to stop it happily churning shares until zero , a real fund manager might have spotted the problem in the first year )
so with an ETF if using a complex formula can start digging a hole very quickly ( or been dumbstruck by an unforeseeable event , like negative $US 43 a barrel oil )
will dig into the links
thanks and cheers