Here is my first attempt to make an illustrious realistic model.
it use my mklan-Illustrious model as main which is merge with :
https://civitai.com/models/1257570?modelVersionId=1488590
https://civitai.com/models/958009?modelVersionId=1517097
and one other that I can't find here.
the result is quite pleasant and do depends on your settings, so check my samples or try your settings.