Hi,
I have some remarks

Split R2 in 15K than 4.7uF to ground en 33K to the drain of Q1, this wil help the hum suppression this wil be a small 30dB.
Is the SOA enough for Q1?
Place a 8.2V or a 10V Zener over R14 to protect the opamp in case of short circuit, anode to ground.
If you want to spend a little money, replease the diode D5 with a 10V reference.
The minimum output voltage will be a bit higher, but the power supply will become more stable and will get less noise.
Adjust the value of R14 to get the right ratio again.
If the current value of C5 just keeps the power supply stable, then something's wrong...
The 10nF of the pin-2 and the 100nF over the compensation connection of the NE5534 is really ridiculous...
TipIf you come up with values for components that are far above the normal values during testing, then you know that something is not going right.
C5 is for normal use with gains lower than 3x about
22pF!Above gains of 3x a capacitor in not necessary for the NE5534.
But...This is not a normal circuit, you have extra gain in the loop, so compensation for a stable regulator wil be far more difficult.
Yes C7 helps :-) but that is nog good enough, and no do not make this capacitor higher in value!
You have to solve the problem where it arises and that is the gain or Q1.
Place a resistor and a capapcitor in series from the Drain van Q1 to ground, this wil lower the gain in the loop.
Try to find out for yourself which value's ar needed.
As a starting point you can take the value of R2 which is the dominant part of the impedance of the drain of Q2.
Q5 need a small base resistor, 100-Ohm or so.
You need a Zener to protect the Gate-Source voltage of the power MOSFets.
Place direct on the gate of Q1 en resistor, say 150-Ohm.
Kind regads,
Bram