Cookie Bars and Ingredient Swaps

My family really enjoys these cookie bars: https://sallysbakingaddiction.com/soft-chewy-chocolate-chip-cookie-bars/

I made a batch last night for the first time in a while. I can fit them into my calorie budget as they are, but I was thinking about ways I might adapt it to be a little less calorific. The concern I have is mostly about the texture, since that's so much a part of the experience of eating these. I was thinking about using applesauce or even shredded zucchini for some of the butter, which is something I've done for quickbreads, but I don't know how that would go here. Other ideas include reducing the sugar (which I've done for several other recipes but not this one yet) and replacing some of the flour with rolled oats.

Or I could just find another similar recipe from a more experienced baker who knows how to swap these things!

Any ideas or favorite bar recipes?