No. 9: Pascal Siakam, 18.2
Three players in the history of the Toronto Raptors have made two or more All-NBA teams: Vince Carter, DeMar DeRozan, and Pascal Siakam. Of the three it's without question that Siakam was the best defender, and he is also the only one of the group to win a title in Toronto. That's part of why we argued for Siakam one day getting a statue outside of Scotiabank Arena, even if the odds are very low that would ever happen.
Why does Siakam rank where he does on our list of the best players according to PER? The reason he doesn't rank higher is that he played real minutes early in his career as he was just getting his footing, so that pulls him down a bit. If you take out his first two seasons, Siakam's PER mark jumps to 19.1, and would rank fourth among eligible Raptors.
What about Siakam's game lends itself to strength in this metric? It's likely the way he contributes in every box score category. Unlike DeRozan, a one-trick scoring pony for most of his time in Toronto (his playmaking really picked up mid-career, to his credit) Siakam contributes in nearly every area. For example, in that year 3-7 range we looked at above, Siakam's per-game averages are stout: 21.5 points, 7.5 rebounds, 4.4 assists, 1.7 steals and 0.7 blocks across five seasons.
PER doesn't do a great job of evaluating defense, but even so Siakam's defensive impact plus his versatile and wide-ranging offensive game propel him into the Top 10 on the Raptors' career PER rankings. He is now a member of the Indiana Pacers, but while he was in Toronto he was one of the best players they ever had and was integral to bringing home the 2019 championship.