I don't think there are any real cons. I usually play variations of 3-2-2-2-1, used to be the butterfly but now usually one of the two formations I mentioned above, depending on where I want to attack. Usually I play with red arrows on AMs, blue arrows on DMs. MCs can be either red or blue, depend whether you're stronger or weaker, and want them to help out more with attack or defence. If I really outclass the opponent, DMs can just play with no arrows.

This is how I play against stronger or equal opponents:

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Against weaker opponents:

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Focus passing depends on your formation, though.

If I'm playing defensively and counter attacking, passing is always long. If I'm attacking, then mixed passing for wings, short passing for through the middle. Tackling can be easy against much weaker opponents.