Posted schematic and PCB on Reddit for a design review - https://www.reddit.com/r/PrintedCircuitBoard/comments/xo5yta/design_review_audio_visualizer/

• Add stitching vias to the ground pour
• Use the thickest traces I can get away with
• Don't daisy chain the power connections, use star formation
• Be mindful of physical construction of the plugs
• Move capacitors closer to the IC it is supporting
• At 0.1uF Low ESR caps to power pins of op-amps
• R82 & D71 should point downward, not to the right. (in the schematic)
• J2 (DC power jack) should have reverse voltage protection
• Add high impedance input buffer to filter section to avoid unnecessary loading, such as a JFET op amp, could also just use extra op amp in each filter section as the buffer
  • If I don't use the extra op amps, consider tying them together