Dava picks- my local guitar store steered me to the Dava "grip tip" picks. My problem was having the pick fly out of my hand while picking, and rotating in my hand while strumming. The Dava picks have a "bumpy" rubber coating and have a noticeable difference in stiffness when you choke up on the grip.

I have a bit of arthritis in my picking hand so this really helps out a lot.

I'm not familiar with their other offerings but I've swapped totally over to the grip tips.