The main goal here is ecommerce, so we want a practical banner(s) which do a good job of showcasing what we have to offer - this can best be done by including a few product images which represents the range of what we offer. A secondary goal is branding, so it's important for the banners to reflect the clean and minimalist look/feel of the website as much as possible.
For copy, we don't really have any slogans on the site but in Adwords we use the terms 'Utility Chic' which you can use on the banners, but you can also incorporate selling points from the product descriptions
Feel free to get creative, as long as these 2 main points are fulfilled:
1) Overall look/feel matches the website and brand
2) It's clear what we're selling (ie. it needs at least 1 product image - the image on the homepage may work best though)
These banners are for remarketing in Adwords, so I need all the standard sizes for that.