Hey it's a different and novel approach, but I can not see it working efficiently in that you will not reach acceptable / comparable extract.
Basically you are trying to simulate a mashtun and lautertun combination. With beer you agitate the mash and heat for the various conversion steps. Post that it would pass to the lautertun and then onto the wort kettle. So in your case there is no mash for agitation because it has been left behind in the extractor. Also there is no real bed to drain from / through, nor is sparging possible. Ultimately there are going to be terrible losses to contend with. Worst of all, there is is a tonne of spent grain to remove from the extractor.
But a great effort and you won't know it until you try it.
I have often thought about this and I would have performed all in the kettle and then considered placing a strainer post the kettle whilst pumping / transferring to another vessel for spent grain removal and prior to cooking (wort kettle) and then transferring back to the kettle.
That's my sixpence worth.