I am in complete agreement with you. I had to buy a new washer a month ago since my 13 year old GE broke. I was surprised when the salesman told me that it probably wouldn't last more than 6 years. He said that all the washers are built much cheaper now. I ended up buying a Maytag high efficiency washer just like you. Just like the new ovens, it has a lot more electronic controls that limit what you can do.
Back to my new GE convection gas oven (not Profile). I compared the specifications of my oven with the GE Profile oven and they are identical in all the important areas. It turns out that I can set it to 550F. When I tried setting it to 550F using the convection fans, it automatically lowered the temperature to 525F. There is a special conversion feature that enables you to disable that, which I did. There is also a special feature that allows you to adjust the thermostat plus or minus 35F (I haven't tried that yet.). With these two features, I should get the temperature I want.
I tried my new convection oven yesterday with my soapstone in the second to lowest shelf and it came out good. I'll have to try different shelves to see what effect they will have. If I tried using the second shelf in my old oven (non-convection), the top would not have cooked enough and I would have to use the broiler for a few minutes. However, with the convection oven, I didn't need to use the broiler.
I once tried putting my soapstone on the bottom of my oven (no shelves), which is directly above the burner. I measured 760F with my IR thermometer which is way too hot.