A higher resolution or the use of image enhance upscaling is recommended for images with smaller eyes or none face portraits. Not 100% necessary but can help in images that don't have hearts.
A v2 is available however I'm not sure if it performs better then the v1 a lot but will properly do glasses without breaking them more consistently.
v2: https://pixai.art/model/1661296211013279784?utm_source=copy_web
