New advances on cryptography such as Zero-Knowledge Succinct Non-Interactive Argument of Knowledge (zk-SNARKs) are a step in the right direction to allow others to validate a transaction without them knowing the details of the transaction.
Related with the previous cryptographic breakthrough is Homomorphic encryption which allows to perform mathematical operations (for example: addition, subtraction) to encrypted data.
The concepts mentioned before as the basis of the new way to design information systems and will have a measurable impact on the decision to use blockchain in a production environment.

Using this technology, blockchains document the actual values. They document in real-time the financial standings of its owners. Accordingly, if their owners approve, it can be used by interested third parts for real-time monitoring. Values are more than currencies, it can also get applied for certifications, interlectual property and licenses. With this, it makes blockchains attractive for procurement departments. Besides prices, the potential client can have complete transparency about the providers certifications and licenses and due to this, can decide if not only the price is competitive, but also if the company has the ability to execute the project in time and quality. If blockchains get implemented for products, it would be possible for the buyer to get a better understanding not only of the ingredients, but furthermore, where they came from. Unwanted content can be identified, this can mean gluten or even new slavery and conflict minerals. Uncertainty about the claimed fair-trade get can get excluded.

The ‘layman’ view of ‘privacy’ is that I, the ‘layman’ - own both my identity AND the transaction data that my identity generates. A view reinforced daily by marketers, ‘paying’ to access that data via either ‘discount offers’ or a direct payment to a data miner. The technology view is that identity and transaction data are different things, and that I, the ‘layman’, own ONLY my ‘identity’. The game stopper is cultural change, and the associated corporate social responsibility.
A permissioned network is a monopoly, charging a fee for entry into the magic circle; either as a transactional commission, or as a ‘new partner’ equity contribution. The model prospers by generating an overwhelming individual ‘value add’, and addicting users – with every user paying – one way or another. The game stopper is ‘no fee, no play’.
The message of the above paragraphs is that whatever guide is developed, it must 1) address the ‘game stoppers’ of the various stakeholders; and 2) take on a phased approach that progressively integrates ‘like-minded’ stakeholders over time. As time and experience with the technology accumulates, the easier the integration process becomes - eventually resulting in a robust ‘bottom up’ guideline that covers the interests of all stakeholders.
Break it into a project. Identify the stakeholders in phase I; determine their ‘game stoppers’ in phase II; propose a draft guideline, progressively iterate, and integrate over phase III-X.