Best Counters To Light

I'm relatively new to the game, I only started playing about a month ago and just reached level 45. When I started playing it was alongside 2 friends who have both since pretty much abandoned the game and only reached level 30. If I can convince them to play, it's never more than 2 games before they're fuming at playing against lights.

So what are the best Counters to light? I've suggested the usual of glitch traps and grenades but not sure what else to suggest. They're actually pretty decent players, always having a positive K/d and racking up good objective or support score (usually both), they just can't stand getting killed my lights. My own personal beef with lights is actually more playing alongside them, as they run away too fast!

They've agreed to try get back into it for season 4 but I want to try and keep them on it. I also suggested they maybe just play when we're all on as I think when they'd be solo queuing is what has soured them on the game.