Jears

You will always need some sort of oom killer unless you have endless memory (or swap space, which comes with its own problems in the form of grinding your system to an almost halt). Imagine all memory is in use, then some system critical task (or even the kernel itself) needs memory as well. If the kernel can’t kill a less important process to free memory in such a situation you might just crash your system.

and you can afford to lose everything in the case of a power cut

But ext4 is a journaling filesystem, so a power cut shouldn’t harm it.

I have no idea about apple design guidelines and am not a UX designer, but wouldn’t a horizontal seperator look better? In gtk i would add one here, gives some extra space and more visual seperation.