WINGERS
One of your players should be trained as a set-piece beast. Massive shooting and crossing.
Besides that, focus on speed and fitness primarily for wingers.
After that fast counter attacks, to boost the players assist potential. What i've experienced is that if the wingers have good passing/crossing, it results in my strikers scoring more.
STRIKERS
I'm not having problems getting my strikers to score. I believe strikers got buffed with the new update, as last two seasons my top scorer was a striker, and my #2 scorer this season is my striker, whom has 32 goals already.
Basically, want a big physical striker, with good positioning, heading, strength and finishing. Strikers job is to be a target man in the box on set piece and find a way to get himself open in the box when my wingers are making a run. Wingers job is to deliver a good pass to the striker(s).