I know that 1kg is about 2.2lbs but that still doesn't give me the "mental clarity" of what 20kg is unless I do the conversion.

At the gym I use the pound plates and not the kilo ones. I intuitively know what the difference between 135 and 225 lbs feels like, and I don't have that same intution for kg.

All that said, I don't find the "small dog" types of analogies for weight very useful. Why not just use the same number of characters (or less) to give the weight in the other popular unit?