What I do think would be helpful is if online retailers of clothing used models that were more representative of their target market.
So River Island's models would be 18-24, size 6-8 and 5 feet 8 inches.
Oasis' models would be 24-30, size 8-12 and 5 feet 8 inches.
M&S' models would be 40 - 60, size 10 - 14 and 5 feet 6 inches
When I buy a dress from Warehouse I always note that the model is a size 10 (great) but 5'10" four inches taller than me so I always cover up the legs
to get a better idea of where it will come to on me, length-wise.
Personally, I think Boden hits the mark with models for its target audience who tend to be around 30 and very slim.