1) It's a bad idea to attach ANY turbine to this system. The water that's in this system is closed, meaning that it consumes and produce exactly the same amount of water. Overheaters requires 10 water each and the steam turbine produces 20 water. That means if you attach another turbine to the overheaters, it will use up all the water and your system shuts down.
2)You cannot attach any sort of water pump to the system, aside from one to start it. Again, since it's a closed system, the steam turbine will produce 20 water every time it 'crafts' hydraulic fluid. Therefore, if the pipe network that the turbine is connected to are full of water, the steam turbine cannot get rid of its water and thus cannot craft further power.
I highly doubt you NEED 2 of the 3x3 boilers, but I wanted it to be symmetrical. I don't know that kind of recipe you're thinking for these machine, but they need to be significantly expensive as they offer quite a lot.