For fun, I broke down my spreadsheet some more to only display gift card churning. On average, my return is about 95% of the gift card value and I have spent about $180 after cash back with purchases over $4000.
Cardpool has the highest return because I maxed out the 4% back with them through TopCashBack. I would expect that number to drop as I sell more cards with them and because I am ineligible for cashback.
How are you doing on your gift card churning? Is anyone interested in using the template that I use? I could post it in the Google Documents/Drive