It's potentially Miller, who has been above 1.0 PPG since being traded to the Canucks, at 50% retention for the entire season. I don't understand the recency bias angle when it's 3 years of data that supports how he has completely outperformed his contract and been a huge line driver. It matters that he was top 10 in scoring last year - Canucks shouldn't trade him for cheap.
Marian Hossa was traded to the Penguins in 2008 (with Dupuis) as a trade deadline rental for Christensen, Armstrong, Esposito, and a 1st round pick. At the time of the trade, Esposito was still touted as a top prospect, Christensen was a solid 3rd liner, and Armstrong was a good 3rd liner who scored something like 40 in 50 games 2 years prior.
Hossa had no retention and again, was traded at the deadline. Similarly he was a top 10 scorer a season prior and was 29 when traded. He had a BIG return. Imo it's a fair comparable with Miller except Miller can be had for the entire season at a fraction of the cap space.
So yeah - Canucks absolutely want to get really good young pieces and picks, they're giving up someone who was top 10 in scoring last year and who can put a team well over the top if salary is retained.