Customizing the append details form?

Has anyone had any luck customizing the append details form? The design is abysmal. The grid has a lot of info in it and all they give you is the tiny screen with 4 huge grids, and they aren’t moveable or anchored correctly so you can’t expand them, and when you try a personalization, they go wonky on you. I tried a customization to try to set the size and remove the anchors to try to get it to work right, but I can’t figure out how I would deploy that customization to that form, even if I did get the customization to work. YUCK!!

If anyone has done this and has any tips, that would be awesome.