Just a comment about C3 and C2. I dont want to start a flame war about this but I would not remove those capacitors from the circuit and this is why.
Removing those will enable track and wire inductance to act as an open circuit for very small time. Hard to explain but here it goes.
Current in an inductor increases with time. At t=0, when mosfet switches off (t=time) the inductor will be an open circuit. This would be very bad for your mosfet as the voltage spike created by the boost converter will have no place to go, thus nothing to clamp that voltage down. That situation might enable that voltage to exceed your mosfet's Vgs.
Another thing is that with such a fast dV/dt (rate of change of voltage) the parasitic capacitor between the drain and the mosfet gate will create a voltage in the gate. This is very very bad as this voltage will turn on the mosfet when it should not be on.
If you make the path from your mosfet drain-diode-C3 very very short you will be running on the safe side as this huge spike's energy will just be stored in C3. C3 will not let the voltage spike so high then.
It is extremely important for the survival of the booster that the output inductance it sees is minimal, and that is achieved by shortening tracks and adding capacitance.
I am not great at explaining things but I hope you get the idea.
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