There are no strong or weak formations, its what to use and when to use depending on your situation and strength.

Facing stronger opponent? Defend and counter.
Facing weaker opponent? attack and press
Facing same strength teams? Control possession, look for opponent's weakness and gaps.

Look at your formation and visualize whats needed when setting up tactics. If the players are spread out through whole pitch, press whole pitch. If the gaps between players are minor then use short passing, long spreads between them use long passing. If there are fullbacks and wingers on both sides then use flank passing, if they are packed in middle then pass through middle. Offside traps are used with whole pitch pressing, counter goes well with long passing, short passing work well with packed midfield, zonal marking should be top choice unless your formation is exact as opponent which you can use man-to-man marking.

Arrows should not be abused, they should be used to change up play, fill in space and direct purpose to gel your formation and tactics together. Example red arrows on fullbacks and wingers when attack down flanks looking for overlapping runs. Red arrows on AMC if you want him to pop up in the box as 2nd ST. Blue arrows on players when you need to see out games, put in more defensive work when needed. Blue arrows on ST maybe used if you want a False 9, making your ST drop deeper to dictate play.

These are just some of the basics all managers should fully understand. If you guys are interested I will post up all the formations and all the tactics that go hand in hand for reference.

BTW. Forget that BS that you need a DMC to block an AMC, DMR to block AMR...blah blah blah...Why worry about defense all the time? Why not try to use 3 MC to cut off connection of the AMC with his teammates? If some1 has a DMC, I will put in an AMC so I make sure the opponents DMC will be busy and stay low instead of letting him roam freely to link up defense and attack. Please comment your thoughts and hope this helps all new managers.