Ouch, have not thought of it.. Thank you for the warning!
Definitely should go with 10k + 100k.
A capacitor on a ADC input it is a good idea too.. On MAX6126 voltage reference in the datasheet they recommend a pair of capacitors 10uF and 0.1uF on its output.
Will try putting same combination on the 'lower' line of differential input.
Thanks again!