Meeting with advisor (9/5): SDA equations

I asked my advisor about which way of decomposition I should use? There are many ways of decomposition. For example, total energy use can be decomposed to as simple as final demand change effect + input requirement change effect + joint effect. Or it can be decomposed to much complex equations including capital, labor, material substitution effects. Or it can be decomposed including effects from trade. It really confuses me. Which way is better to explain my topic? His advice was to start with the simplest one, then add more decomposition equations. Right, I have to start, although I don't have a perfect blueprint.