I learned a new tension trick too...last night. But I'm such a beginner I'm sure everybody knows already.
When switching to a walking foot from a regular, open toed, or 1/4" foot, leave the foot attached to the ankle/shank area. That way you don't lose that tiny ankle piece. Also, when using a walking foot on thick stuff, like your whole quilt sandwich, it can be helpful with the even feeding to make your stitch length a bit longer.
I piece at 2 or 2.5. Raised it to just over 3 last night and it worked great.
Just a thought!