Ebay is going to do what it takes to make your pics 400x400 pixels. I've seen them crop, shrink and distort to make that happen. There are a number of free online hosts for photos, and I highly recommend
www.robshelp.com as the place to go if you want a nice Ebay auction template.
As a regular Ebay shopper, I'd like to see a little more discussion of coin condition in your auction. You can include as many photos as you want if they're hosted off-Ebay, and a couple closeups (personally, I'd want to see the '27-D and '30-S) would go a long way towards the sale.