I think it needs to be a lot more clear what bitshares actually is. If bitshares was just an iteration or improvement of some existing tech that the average consumer knows about, then it would be feasible to sell it mainly on emotions through pictures. But the closest we can get to that is to write that bitshares "is like bitcoin" or "bitcoin 2.0". That will probably still not be enough to prevent the average user from bouncing from confusion.
It sucks, but I think we will have to explain some fundamentals of the the system right on the first page, and will thus need to use a lot more text. Unless people are buying into a third party centralized service that holds bitUSD for them, they need to understand that bitshares are distributed and decentralized with no issuer or owner, so there's no risk of an owner running away with their money, but also no official support, insurance or guarantees.
I had an idea that one of the ways we can communicate the public key crypto that powers our system, is to market to our users as "owners". So you're not a bitUSD user, you're a bitUSD owner. An owner can never have his funds seized, frozen, snooped on or restricted in any way. You're only an owner if you control the private key. We can do an emotional sell by playing on this as something that should be a fundamental human right: if you've earned something through honest work NO ONE should be allowed to take it from you.
I think a good source of inspiration for the visual style would be the style of graphics used in the weusecoins video. I especially like the pacifying colors and that each feature has its own unique icon (and even sound), it quite amazingly done.
Here are some random ideas for how I think it could be done in the current style. These are just quick suggestions and written in haste, but maybe some of the ideas are useful.
BITSHARES - a bank without bankers
DECENTRALIZED (picture: stylized drawing of a meshnet) - Bitshares is powered by all its owners, who work together to run the software that maintains the system across thousands of computers. This ensures that there are no intermediaries between owners and that no one have the ability to change or steal from the system.
OPEN SOURCE (picture of whatever people positively associate with open source) - The open source software uses the most reliable proven cryptography to ensure that an owners funds are always safe and spendable only by him. Every line of code is public and can be audited by anyone at any time.
STORE OF WEALTH (gold bars) - You can deposit money into bitshares in many forms: bitUSD, bitEUR, bitGOLD... Each of these tokens always hold the value of their underlying asset, and pay an interest rate (currently x%). Everything is collateralized at 300% of its value by the highly liquid backbone currency bitshares.
LOW FEES, NO RESTRICTIONS (stylized broken or frozen bank)- Using bitshares you can send money in any form, directly to any other user anywhere on the planet within 10 seconds for 2 cents. You can also exchange currencies and assets instantly and at low fees. There are no restrictions, requirements or authorization needed for the owner to send and spend his money as he wishes. Transactions are private and no one will know how you spend your money.
BE YOUR OWN BANK (picture of sympathetic person) - these features allows anyone to store their money with total privacy in the way they decide, out of reach of getting stolen, frozen or seized. Finally you can own what you own.