If I were the GM of a new team, finding a QB is an obvious answer. Good luck with that in year one unless you can steal a former backup like Trevor Harris or Zach Collaros from a team.
O-line would be the 1st priority, even average QB's look good when protected properly, so technically Oline is more important than QB. QB would be second, someone with good awareness and Football IQ even if I had to sacrifice his initial physical "build". Above average throw power with good accuracy within 1-20 yards to start. The deep ball would be developed.
From there you find an above average deep threat slot back, and good possession receivers (receivers need to be Canadian). And then I would look at the defensive line and try to find a great pass rusher and a big balanced DT.
I would then look at finding some prototypical linebackers who are okay in zone coverage but can also fill in on the run.
Finding two good defensive halfbacks are paramount with at least one good short side corner. After those are found, try to find a rangy Canadian safety if possible.
From there, go back to working the rest of the D-line and build depth their for rotation
(notice I haven't said running back yet?)
Finding good special teams players are next, Kicker and then Punter, and then various depth players
Finally I would scout and look at running backs. The reason I have RB at the bottom is that they are a dime a dozen. Players like Jon Cornish, Adrian Peterson, Mike Pringle, LaDanian Tomlinson, Marshawn Lynch, etc. Are very rare for their longevity to dominate and hold the position for more than 6-7 years in either league.
The reason is that you can always find a cheaper and almost as or just as talented option whenever you want.
From here, I would fill in whatever else I needed.