I'll take Forsberg. He was a better all-around player at his peak, while Yzerman focused almost entirely on offense and lacked much of a physical punch. Yzerman may have put up 155 points but, if adjusted for era, his offensive peak isn't really all that far off from Forsberg. Where they differ is that Stevie Y didn't become a defensive stalwart until much later in his career.
I agree with your general summarization, however, there was a short but distinct dearth of offensive superstars around the NHL in the late 80s/early 90s. It was guys like Nicholls, Mullen, Carson, Robitaille and Brown near the top and most of the top scorers played with Gretzky and Lemieux (or on the Oilers).
It wasn't until Lindros, Sakic, Forsberg, Jagr, Selanne, etc. started to take over the scoring stats that it was harder to pull away from the pack, which might not favor the optics of Forsberg's dominance. With their adjusted numbers being in the same ballpark, I do actually think Forsberg's two-way play makes up for it. Forsberg was also a much better playoff performer at his peak, while it took a while for Yzerman to put it together.