I believe that the markets will produce results independent of any individuals political concept of what is 'good' or 'bad' and that attempts to engineer a proper-balance between privacy and transparency will likely fail, it is like trying to mix oil and water.
In the case of BitShares X, the privacy consideration is more or less identical to Bitcoin.
In the case of Keyhotee Wallet, it will add increased privacy to both Bitcoin and BitShares X through dividing one transaction with many inputs going to one output into many transactions with a single input going to a single output and entirely eliminate the reuse of addresses. This process will make network analysis much harder.
In the case of Zerocoin technology, I have played with it and would like to integrate it in a future product.
As far as the Short, Poison, Profit potential is concerned, this cannot be prevented... see 9/11 for an example of people who did this with our current system and yet were never caught.
A business would counter this kind of attack with insurance which would make the Short, Poison, Profit attack backfire as it would yield profits for the company rather than losses. If the company attempted to perform a false-flag to commit insurance fraud you are no longer dealing with anonymous individuals!