Analog problems often look complicated long before they actually are. Start by checking the quiet basics.

• Are your references, rails, and grounds doing what you think they are?
• Did you budget source impedance, bias current, settling time, and ADC acquisition time?
• Is the noise really analog, or is it digital activity coupling through layout?
• Did you verify startup, load step, and thermal behavior?

For mixed-signal boards, I care far more about return paths, placement, and measurement technique than decorative schematic neatness. If you want useful feedback, post the relevant schematic section, rail voltages, scope captures, and a short description of the expected operating range.