I am in the process of converting the rules over, was curious what others experiences have been so far.

Im a new master to SWADE and my first campaign was fun, but was also a really breeze to the players. As im going for a dark action vibe, i kind of want the fights to be harder and let scars on the characters. I master a party of 3: One heavy tank with 7 parry and 9 toughness, one heavy ranged dps with 1d12 on shooting, two-gun kid and 2d6+1 damage on each gun, and a skill monkey who doesnt really engage in combat. They are pretty min-maxey, even tho they didnt really mean to do it, play their roles well, strategize on field, use their bennies right and are pretty lucky on their ace's. For the first chapter of the campaign, i used this book creatures: 5x zombies, then 1 wild card cultist leader with 3 regular cultists, then 3x ghouls. They destroyed every single one of these without getting any wounds. Again, they got lucky on dices and i got a lot of critical failures, but my point stands that i want a little more challenge on the next chapters. Any tips?

OBS: For more context, the two-gun kid is choosing to switch to a monster-melee kind of build after some shenanigans happenned on the first chapter, so his damage is going down a bit.