I made another cheddar yesterday and finally got a good knit. Tested my dutch press to the point of destruction again, this time just an eye hook unbending. Last time I cracked the wood out of my upright where the lever arm anchors. Reinforced everything and doubled up the lever arm. Got about 9 psi. The last time I had under 4 psi, and I could see the lines between the curds, more so as it dried; kind of looked like yours. It's still aging, so we'll see how it tastes. I vacuum sealed it since I didn't look like a good candidate for a natural rind.
Dave in CT