There are a ton of vids and suggestions out there to cure a slice (I'm sure you know this haha). What worked for me were two things:
1. Torso tilt at address. Moving my spine angle from upright to a few degrees behind the ball really helped me get an inside-out rotation. For illustration, I went from this "I" to this "/".
2. Closing my stance just a tad.
Every idea out there is basically trying to get you to do the same things you already outlined. If you have a slice, though, your swing path is still outside-in.
I was hitting a lot of pulls and occasionally pull-hooks at first, but after swinging easier for a bit with the two things mentioned, began hitting high draws and have been doing it ever since.