I agree with the idea of a fixed-term regardless of life but 5-years is too short.
My proposal has been requiring authors to take affirmative steps to get a copyright (it's not automatic or free, though the fee is nominal), so that we only have to worry about the works the author specifically wants to protect, and that the terms would be 1-year with renewals. The number of renewals would depend on the type of work, but in no event would be all that long.
There was a study some years ago that suggested that 15 years was optimal in general. I'd like to see more investigation of that.
With a short, fixed term like that I would also extend a "character-right" for the life of the author i.e. give them exclusive rights to author more books set in the same setting/universe with the same characters so that only they, or those they authorize, can write sequels to their works while they live.
Strong disagree. First, life terms are too unpredictable (and might be shorter than fixed or renewable terms of years). Second, part of the goal of copyright is to encourage the creation of unauthorized derivative works; that's why we have limited terms to begin with.
If an author writes a series of books over years in a common setting, with common characters, the first one entering the public domain only opens up the setting and characters as they were in the first book; third party authors can fork it -- instead of the character of John Smith remaining in Everytown USA on his farm, which was what the original author kept writing about, the new unauthorized one has him set out on magic spy adventures in space. The market can sort out whether this is popular or successful.
This sort of thing has worked out okay before. The Aeneid is just the pro-Trojan, pro-Roman fanfic sequel to the Iliad. (Virgil: "Turns out some of the Trojans survived the war and escaped and had crazy adventures! Let's follow them instead of continuing with Odysseus or Agamemnon.")