A bit of perspective on component selection: as far as audible performance goes, the only parts that matter are the capsule and op-amps. If this were food, the capsule is the cut of meat and determines the flavor. Resistors and capacitors are the choice between table salt, sea salt, or kosher salt. You will have to listen very closely to distinguish between them. For example while it is known that non-polar aluminum electrolytic caps distort less than polarized ones, the distortion is so small it can't be measured on most circuits. It is lost under other non-linearities. I wondered if this mic and my interface were clean enough to detect the difference, and surprise!, they are. But notice that test was run injecting the test tones directly, and no capsule was connected. I didn't bother changing the caps on the other boards because the distortion is inaudible.
Also note that the boards I tested were laid out and built by Homero Leal. (Thanks, Homero!) They are similar, but not identical to Jules' layout used by JLI. It turns out with the huge open-loop gain and wide bandwidth of modern op-amps, board layout and grounding matter. In my experience a lot of the rules "everybody knows" about audio grounds, such as single point star grounds, don't apply. There just isn't enough current or power involved with phantom power, and more important are solid contacts and shielding. A filled ground plane on the circuit board with plated through mounting holes so the PCB ground is solidly connected to the mic body is less troublesome than depending on a single point such as the screw of the XLR insert. Tube mics where more power is involved are different.
C0G MLCCs are preferred in audio because they have near constant capacitance with voltage. They are still microphonic, though less so than X7R and other class 2 MLCCs. The high-capacitance dielectrics generate 3rd harmonic when used in filters where a variable signal appears across the cap. In straight DC blocking service, where both sides of the cap rise and fall together, distortion is minimal. Capacitors are slightly microphonic, but a mic capsule is VERY microphonic. If the circuit board is reasonably secured to the mic body, microphonic caps aren't a worry. Note that film caps are usually microphonic, too, and they are not tested for it. The electrodes move slightly, just like a condenser capsule.
In short, your choices are fine. You should have a fine mic when finished. Audio electronics don't usually require extreme precision. In fact, a lot of it is deliberately distorted to replicate some ancient piece of gear that is now rare and expensive. You'll find analog electronics interesting, and some of it will open your eyes for digital design as well. After all, signals on a digital PCB travel as analog voltages.
