A thimble because pushing a needle through tough fabric can be painful on your fingers.

I have a little knipex plier wrech in my edc kit that works nicely for grabbing or pushing a needle. The gripping parts (???) are flat so they dont mar the needle.

Not OP, and I suck at hand stitching, but I usually use the thickest stuff I have on hand to account for the reduced stitch count. Also because I like how it looks.