Humaaans - Mix-&-match illustrations of humans with a design library.
Handsome Illustrations - Create unique illustrations for websites & applications.
Craftwork - A collection of User Interface resources made by Craftwork
Control Illustrations - 108 free flat illustrations with customizable characters
Open Doodles - A collection of free sketchy illustrations
Ouch! Illustrations by Icons8 - Professional, perfectly matching, and customizable illustrations for any designs