To my eye... and I'm certainly no scout... I don't see how you'd project Zadorov to be significantly better offensively than Morin. Zadorov is more physically developed and played for a more storied Juniors program. Offensive development just seems like a complete projection (like picking goalies) for both players. Sure there are tools that you see on occasion, but how you speculate that that leads to 20 points a season or more in the NHL? No clue how you'd say that.
By way of comparison, Nurse was vastly more productive and it's still speculated whether his offense will project well in the NHL. There's really no conversion to speculate about with Zadorov or Morin. Not saying it can't be there, but the Flyers scouts would be putting themselves out on a larger limb than most picks with either of those guys at 11 imo.