Depending on the opamp used, input coupling caps (in series with the input signal) may be advisable to prevent DC bias current from going through the cartridge coils.
The loading caps (going from inputs to ground, in parallel with the 47K resistor) for MM cartridges depend heavily on the cartridge itself. The ideal value varies, and the tone arm cable/interconnect cable from the turntable cable capacitance must also be taken into consideration. The total value is typically in the several hundred pF range. Too little capacitance and you'll have a peaky HF response, too much and the HF response will roll off.
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