What kind and brand of thread would you recommend for machine piecing?
For machine piecing I LOVE the Essentials thread from Connecting Threads. Its inexpensive, can be a bit linty, but for the money is the best value. I have a Pfaff 7570 and a Babylock and have a Singer 201. Works in all of them just fine.
I use the thread from connecting threads and or Coats and Clark. Either one works great for me.