The issue is that F was really meant to be on the Upper Deck not on the lower deck. No one knows what to do with large space on either side of the stairs otherwise. MH A380 F has the same issue. EK put their showers there

The best toilet sizewise I have been in to date has been the AA toilet near 2R on their 777W planes. AA 777W planes have four toilets but come in three different sizes; in true Papa-bear, Mama-bear and Baby-bear sizes.