Mike
Firstly - Thank you for your efforts to persuade the CAA to provide a raw data feed.
But I'm not sure I entirely agree with your arguments on the commercial nature of NOTAM provision. It seems to me that if anyone has to pay for NOTAM distribution then it should logically be the originators of the NOTAMs - they are the cause of the "problems" so they should be the ones to pay. Obviously this is a complete non-starter for safety reasons, but I don't see this automatically means that we should have to pay to receive the information. If someone wants to reserve a chunk of airspace for their own use why should I need to pay to get a map of where it is?
Secondly there is an important distinction between using the NOTAM data for personal information and re-distributing it for commercial gain (however small.) In the second case it is reasonable you have to pay a fee, but not I think in the first case. In fact, this is the situation that already exists. NATS terms and conditions state that you must not "modify or download the Website or its contents (except caching or as necessary to view Content)." This is the important element in avoiding the unfair situation you mention, the format of the data seems to me irrelevant.
Your idea of a free, but restricted service, for the leisure pilot seems a good idea if it gets around the problem. The best of luck getting the CAA to agree.
Cheers,
Alan