The advantage though is that even if you don't know the word, you can guess the meaning if it contains familiar character(s). Also except for the first one, your examples are easy to distinguish.
Yep and no. That's a common misconception. Like Chinese, old Japanese went through a systematic simplification of its kanji 100 or so years ago. The rules were decided a priori to make the job easier. This meant that several kanjis ended up looking somewhat similar even though they have nothing to do with each other. That's why comparing kanji can work but it can also backfire and lead you astray.
