RE: 1000mm art tech corsair
Well, there are a ton of options here. First and easiest is to get the 850kv motor from HK, which is a simple direct swap for the 700 that's in there. I have been flying mine with a SuperTigre ST.10 for a while now and have found it very pleasing. It was also a very simple addition - used the stock mount, made up a plywood mount for the ST to adapt to the stocker, and went flying.
If it's overkill you want, then just about anything will work. Of course, you will need battery capacity for something large, and there are a couple of ways to accomplish that.
What is it you wish the plane to do that it doesn't already?