Chaining and then destroying enemies was pretty satisfying. I liked how the chain dragged things together letting you set up some nice quick kills. I did feel like the melee enemies moved/aggro'd a bit too quickly and it was hard to react in time. The cooldown on the chain was also maybe slightly too long as well since if an enemy aggro'd you'd typically want to chain on a box then the enemy (unless you get lucky and they're already right next to a box).
I'm not sure how I feel about health being tied to energy. On one hand I totally get that you want to discourage just shooting since I noticed enemies take significantly more hits to kill unchained. On the other hand it kind of feels bad when you lose most of your health setting up the chain and then you don't actually have enough energy to kill the chained enemies.