Personally I think Russell will do well in a team doing well. Eden at Wire last year would have been an absolute shocker, but at Cas he looked great.
A winger often gets the blame for being out of position, when he's not always the one at fault initially -
sometimes I think Russell got the blame for that.
Every winger in SL is expected to support the forwards, (and Russell is very good at it) - look at McGillvary, often takes the ball in at first receiver for Huddersfield and England. With a more solid defensive line on his inside, I think he would look a much better player. If I were to pick a winger to drop next year, it would be Lineham over Russel any time.