Sorting in Krusader in uniform, but your expectations are different. When you click on the filename column, you (most probably) expect that names will be sorted from A to Z, i.e. ascending. The same is for file extension. But when you click on file size, most probably you wish to see the biggest file on the top. For date fields, you’re looking for the newest file more often than the oldest one. Thus, the sorting must be descending, and you’re forced to click twice instead of click once. If you click once when switch from size to filename sorting, and twice when switch from filename to size, this is your case too!
So, I suggest to make default sorting as descending for the ‘size’, ‘modified’, ‘changed’ and ‘opened’ fields, and leave ascending for the rest. It doesn’t matter, if you use mouse or keyboard.
You might test my forked variant or Krusader, where this idea is hard-coded: GitHub - Vladimyr0/krusader