I helped coach a youth team that my son played in. From day one I told them not to be scared of going in, 50/50, and tackling (taking the ball away from someone elses feet).
They were not the most skillful lads but the opposition always knew they had been in a game against them. Nothing dirty, just being committed and wanting to get the ball. My lad ended up being great at slide tackling (on notoriously soggy, muddy pitches) and winning the ball.
I wish SUFC players would show a bit more "edge", close people down quicker, kick the ball away from their feet, put a foot in before the player gets into our box.