@ I ain't Spartacus
The points you make are made very reasonably. As to life of copyright, most professionals don't get paid for what we did last year, let alone what we did 30 years ago, so I don't feel obliged to pay Bob Marley's grandchildren's pensions simply because I like Bob Marley's music. It would be better for them if they have to work for a living, as applies to older artists if they have not saved any of the money earned while successful as youths. The monopoly of copyright is an artificial privilege granted by the state which comes with costs and obligations for the rest of us, so it should not be accepted as a natural human right.
As I see it the term of copyright should be set to compromise the increase in artists' incentive (which make longer terms more desirable than shorter ones) against the lower transaction costs for new artistic works referential of older works (which make shorter terms desirable). Having shorter terms is of particular importance for the feasibility of cultural heritage, historical preservation and reinterpretation work, a field of artisitic creation in its own right, regardless of the fact that this needs to reference and reuse older work. Having overlong copyright devours our future understanding of recent history, to the extent that the cost of researching and obtaining rights to works long out of publication exceeds the commercial benefit in doing so.
My own take on where these compromises might sensibly lead is that copyright terms should be different for different creative industries, probably no longer than 10 - 14 years for non-recreational software, 20 years for music, photos and literature and 30 for movies and computer games. Movies and software games are likely to need longer terms to be viable, due to the greater costs involved in their creation. But there need to be limits. For the exceptional movie which can still be watched with great interest 30 years after its first public showing this will be described as a "classic", surely a greater accolade to its creators than residual revenue cut off by democratic law through this work entering the public domain at that point. Interestingly, this reasoning awards the shortest duration here for the art I am myself most skilled in. The reason for having a much shorter copyright for business software is because this obsoletes sooner making it unsaleable, and if kept in copyright longer than it is marketable this hinders efforts at digital preservation, both of the software and systems on which this software runs, and in respect of the data formatted by such software which itself is likely to have cultural and historical importance at some point in the future.
Personally I think the need to reward artists will in future be ensured to the extent required by expanding the new commerce in art which becomes possible based on the acceptance of legitimacy of non commercial copying - in the sense that networking services, blank media and consumer electronics and computing equipment sold for the purpose of using this content can then attract appropriate sales commissions, in the same way that we now pay for the music heard in a shopping mall, on the radio or in a restaurant. We are not charged for the music at the entrance to the commercial place where the music is paid, we pay for the music as part of the cost of what we may buy there.
After the failure of PIPA and SOPA to obtain congressional support due to the recent concerted and organised Internet community backlash, I think we're very likely to see further strengthening of opposition to the privacy intrusions and gaggings which extreme copyright enforcement against non-commercial use requires.