Granted, I'm fairly early on in the game still, but so far, I'm having a hard time finding a good balance in combat. I've found that by far the easiest way to take down machines is to simply hide in some tall grass, use lure call, wait for the machine to eventually lumber over to my position and then silent strike.
However, there's two problems with this approach. First, it's boring. Second, it seems the AI is smart enough to catch on after a while, and after you've laid waste to enough of their brethren, machines will no longer come to you.
My alternate approach is to creep up on a machine and then try to put it down through a combination of elemental arrows and melee attacks. This is fairly effective as well, but every other machine in the area will either swarm on your position or run away. The result is that you either end up in an epic battle that you barely survive or you're one-and-done.
Again, it could just be that I haven't progressed far enough, yet, but it seems like I'm missing something. How can I be a bit more active in my attacks while still maintaining some degree of stealth?