I'd ask Rocco Baldassarre. He is the best online marketing consultant I've ever seen and can surely give you concrete advice.

Said that, my advice would be
a) your own e-commerce store so you can drive traffic to it without losing money on commissions
b) learn from best selling products (you can see sales ranks of competing products if you register as an amazon affiliate marketer; it's free) and copy their structure, split test regularly

Hope it helps!