Some bosses are fast, have lightning and tend to come with an army of minions. For bosses like this I find it helps to trap them just beyond their reach. The screenshot shows a good example of trapping a boss. Black Maul is on the raised up way point. If I get close enough to the edge Maul can claw me, so I stand just clear and send hammers flying.
Sometimes the bosses are fast and I end up on the way point with them trapped below the way point. Either method works pretty good as long as you don't get swarmed.
For swarms I use the stop, hammer and run method to take out a few minions. When it's just me and the boss, or me and a couple of minions I try to trap them.
There are still a few minions that are pretty strong, but I find that some of the minions in lower acts are actually more difficult than Lower Kurast.
