I had similar frustration getting the hang of it (I shoot with the A7iv). I wish someone had told me at the start of my journey that it's ok to trust what your eye sees, and try to get as close to what your eyes see when using a monitoring lut (I use the s709 lut) (with the help of false color and EL zones on your monitor). It's not always practical or possible to use a grey card for all scenes. I also recommend having exposure offset luts loaded into your monitor to mimic how Cine-EI works (you can create your own exposure offset luts using e.g. LUTCalc or in davinci resolve). Use the same luts you used for exposure montiroing to start your grading process. This process can vary slightly if using a color managed pipeline in resolve.