I'm sure it's been mentioned several times now, but a solution such as Open Transactions could work well to maintain asset tracking, whilst simultaneously avoiding the "long arm of the law" problems. However, even that I don't think is sufficient.

There needs to be a market forming around an agreeable mediation procedure/technique/ruleset wherein we can arbitrate our disputes in an acceptable manner to the parties involved (it must be considered in the beginning of any engagement and it must be binding, IMO). However even then, I don't believe it will ever be completely solved using crypto-like transactions. Contracts always have a way to be misinterpreted, and participants in markets such as ours will almost invariable have a few bad apples.