Best SA for the top scorer challenge

[iSusel]

I'm a new player and this is my first season. I'm leading the league and have a top scorer but only 1 point and 1 goal ahead of the second place, so I'd like to improve not to lose the lead.
My top scorer is ST/AMR on the AMR position, he has FK SA, and now I want to give the second one. The Corner specialist is good, but not for the top scorer, so the choice is between Shadow ST and 1-on-1... Which will be the most efficient?

Also, what will be the best formation and tactics against low level opponents (~50-70% vs my 90%, often inactive or NPC) to optimize the scoring of the certain player. Normally I use 4-2-3w-1 or 4-2-2w-2 with the AMR in focus, sometimes 3-1-2-3w-1 but even if I get a big win (4:0 or 5:0), the goals are distributed evenly between all AMs, and my top scorer gets +1 or +2, while the opponent (the guy on the 2nd place) has a weaker team but often manages to get +3 for his top scorer, so the lead is disappearing rapidly...

The last game was 6:0 with AML (3 goals), AMC (1), ST (1), and AMR (1)... 5 goals (including AMR) were scored in the first half with Focus passing: mixed. I tried switching to focus right flank, and they almost stopped scoring.