The phrase "sophistication level" refers to how advanced or complex something is. It represents the level of refinement or sophistication in a particular area or subject. Full definition
Check the verbiage for sophistication level, brevity, and impact. (theresumeclinic.com)
For a more polished look with distressed jeans try to wear it with some pointy heels or pointy boots instead of open toe shoes, it ups the sophistication level a notch. (fancycorrectitude.com)
Even this very casual take on a jacket helps up the sophistication level. (themomedit.com)