1) Gilmour would be playing in a team who dominates possession most weeks
The midfielder is an excellent passer of the ball, and he excels when dictating possession from a deep-lying playmaker role. Norwich are, however, facing a relegation battle and they are always on the back foot.
If Gilmour moved to Rangers, he would be part of a side who generally dominate their opponents, much like Chelsea, so he could develop his game in a team who are much closer, in terms of characteristics, to his parent club.