From what I said about a potential improvement for how trust should work:
there should be limits as to how many people can be on your trust list if you are on level 1 default trust. This will prevent the privilege of being on default trust being given out as a "thank you" for your customers.
There should be different formula for calculating positive trust if multiple people give trust feedback that are not trusted by different people. For example if everyone that gives you positive trust are all trusted by badbear then each additional trust rating by someone on badbears list should count for less while someone on theymos' list would count for more. You should not be able to receive "green" trust unless you are trusted by people that are on at least two different trust lists.
-snip-
This isn't really applicable as many persons don't add people who are in Default Trust list to their trust list unless they're making a custom one with depth 0.