Is there a question in here?
You've connected the current sink wrong. The inverting input of U3A should just use the voltage over the shunt resistor as reference.
Test the sub-circuits on a breadboard before you order PCB's. It will catch such errors as mentioned above, and it's also much easier to tweak the circuit for stability, add a capacitor here or there and such.
Maybe you can make the thing smaller by replacing most of the banana jacks with a multi position rotary switch.
Where does your +15V and -15V come from? I see no power supply section, nor do I see connectors for it.
Using 100nF decoupling caps is fine and all, but also add some bulk capacitors, of size 10uF to 100uF, also depends on how you make the power supply.
NE5532 has a worst case offset voltage of 4mV. If you amplify that with 100, you have almost half a volt at he output without an input signal. Is that acceptable?
Consider a opamp with lower offset voltage, or use a trimmer for nulling the offset.
If battery fed, current consumption may be an important factor, so have a look at the current consumption of your circuit.
When you add connectors to the mad and angry outside world you need protection for ESD, EMI and that sort of stuff. When you add (long) cables you also add capacitance, and capacitance on the output of opamps may introduce instability and cause oscillation.
On a box with so many sub circuits it may be usefull to use 2 or even 3 banana jacks for GND. This would prevent the need of those stackable plugs. Those stackable banana plugs are useful, but it's not very convenient if you want to replace the middle plug of such a stack. Using multiple GND plugs also lets you implement star grounding.
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