[Beginner] How do I find a good balance of aggressiveness and discipline when putting in a tackle?

I'm a beginner, I've played about 4 seasons (10 weeks) of 6-a-side, mostly in defensive roles.

I feel like for the most part I'm positionally sound, and stay aware of my surroundings. The one aspect of my game that I've struggled to improve on is putting in a good tackle, especially when face-to-face with an attacking player, or going in for 50/50 balls.

I feel like I either go in too hard and concede a foul, or go in too soft and either miss the ball, or allow the ball to bobble forwards. Generally I'm good at jockeying face to face, but what is a good tip on identifying the right time to put in a tackle, and how do I avoid being strong without being 'that guy' in a relatively casual recreational league?