picture, drawing, painting, sketch
繪 centers on creating a visual representation by hand: a picture, drawing, painting, or sketch.
繪 is the traditional form of 絵. It combines 糸 (thread) with 會, which likely contributes the sound and the idea of bringing things together, suggesting the assembly of threads into a picture.
The left side 糸 suggests threads or fibers, and the right side 會 looks like a gathering. Imagine threads gathered and woven together to form a picture or painting.
For カイ, picture a colorful kite (カイト) made of painted silk threads: kite -> カイ, and the threads form a beautiful picture in the sky.