well, I finally got most of the recommended picks I sent away for.

The wedgies are an interesting design. You don't see it in the flat picture, but the picks are molded in such a way that where the thumb fits is concave, and that material is forced to the other side making it a convex surface, which gives the forefinger something to hold onto.

Because the picks aren't flat, they don't slip!

In addition to the thumb indentation, there is also a knurled surface which also helps prevent sweaty hand slippage. A really clever design!

The WEGEN picks BobC recommended are also pretty cool. If they weren't so dang expensive, I'd try some of their other models.. they have a lot of interesting ideas for sale.

I also bought some of those colored key identifier rings and put them on a bunch of regular ol' picks, and that works REALLY well at providing a gripping area that can't slip while you're playing. But it's a bear putting them on... you almost have to heat them in hot water to get the elasticity needed to stretch that much. But it's a cheap solution... pennies per pick.

Another thing I tried that works very well on odd-shaped picks that won't work with the key rings: I had some thin rubber washers from a plumbing kit... about .030" thick by .625" dia...

I superglued it to one side of a pick. When using that pick, my thumb rests in the middle of the washer, which pretty much makes it impossible to slip.. its the same idea as the wedgie design, where you have an indentation for the thumb.

Since trying all these new pick ideas, I haven't dropped my pick once (and previously I was dropping it multiple times per song... ) this has really increased my confidence that the pick won't drop during guitar solos.

Thanks to everybody who offered ideas! Much appreciated!

https://www.dropbox.com/sh/ey71h8ep047758h/AAC12jNM0Hz9Q8zsh5iDeqNHa?dl=0