Grenade/Trap Ideas

Siphon trap:

Place a small trap (maybe the size of a Wattson node?) that when an enemy walks near it take a part of their Shield or HP and then flies off in a random direction while making a distinct whistling sound..
This trap is small so it is hard to avoid, but it's also not very strong (35-40), plus that it will store part of the damage dealt inside it which becomes a healt/shield pickup. This means that if you're hit you can potentially get part of your life back (25) so it isn't too harsh. You will take some damage and might be spotted tho'.

Swarmer:

Throw a grenade holding a swarm micro drones, that when the grenade lands will search for a nearby target, follow a short distance and if possible latch onto the enemy (torso?).
The drones will slow a player slightly based on how many drones are attached, they can also be shot dealing 1 damage per destroyed micro drone (friendly fire included).

If left alone the drones will run out of energy after XX seconds and fall off.

Wall trap:

When walking over the trap a wall pops up after 1-2 seconds. The wall can be shot through, but you can not pass it. Last a short-medium period of time.

Hack-Trap:
Walking over this trap displays your location on all banners along with a notification sound.

Edit:

Draining dart.:
Throw a dart that sticks to a player, deals 30 damage and stops all energy gain (tactical and ultimate). The dart can be shot away dealing an additional 30 damage or be left alone. If left alone the dart will drain up to 25% of both tactical and ultimate energy.