Are you being Military transfered? You are going to LOVE the Hawaiian quilting scene. I lived in Hawaii for 32years before moving to Tucson AZ.
My first half-dozen quilts were basically one giant log cabin block. I just didn't know that was what it was called. Like you said; start with center block and build around it till you get the finished size you want.
I didn't even measure anything. Using mostly bed sheets, I'd flip one edge of the sheet (to like 4")? and after cutting the length I had a 8' strip. As I made each strip I would sometimes divide the strips with multiple fabrics per strip. Have I lost you?
I've included 3 blocks I made that way recently. It may be hard to tell that they are strips sewn around the center. because the more I make these the more complex they get. It's also my fall-back quilt when I want to relax and not think so hard.