Grrrr ear training and pain in the arse referencing....

[tonyc2002]

Could be a slightly stupid answer....But maybe visually look at a track you know has the "commercial weight" you speak off using a spectrum analyser and then compare it to your own productions? Maybe try some different monitors as well if you can?

Although if you really want to get into the science of creating a good mix then I can reccomend "Understanding and Crafting the Mix: The Art of Recording" by William Moylan. It's good but I should warn you, it's very heavy on the theory side but it does cover everything (including ear training).