for me, eISBs are the best. granted I am using the black ops deck, so that could have something to do with it! I removed vinto from the board in two activations of them, with no other damage source!

My players are learning to hate...and I do mean HATE...Nexu. As stated, they're good for blocking corridors and doorways, they have the pounce ability to let them get in fast, and break up the players when they group up, and they apply a bleed with every attack. Toss in a few probe droids to provide some maneuverable fire, or have them get in close and self-destruct. I've even blown up one or two probe droids when my (Imperial units) would be caught in the blast. Hey, if you aren't willing to shell your own position, you aren't willing to win. I'll also use standard stormtroopers, and reinforce them as often as possible. Toss in a couple of officers for their Order ability to move my friendly units into place quicker. While it's not what one would call 'overwhelming firepower', its enough to slow down the players, and make them waste a round or two taking down a nexu, or a clot of troopers. Add in the right 'seasoning'...such as the card that lets me heal damage to my troopers, and I have a mix that drives my players up a wall every single time.

Break up the players? I'm not sure what you mean by that. (Nexu is not Massive, so it needs to find an empty 2x2 space to land on.)

(I have used a Probe Droid bomb to win Imperial Entanglements, and it's 'fun' in Temptation.)

My players tend to bunch up and move as a group. They aren't on top of each other, but they aren't spread to the 4 corners of the board, either. I try to pounce the nexu's into places where they can potentially split the group, or pick off a player thats sitting in a bad angle.