Wa/Ga aren't that hard. Mostly just subject vs topic. Just like objective and subjective isn't that hard in English. Of course, most Americans can't master objective/subjective.
The trick for wa/ga is often just to remember that subjects are often implied in Japanese and missing from the actual text/speech. So, "Nekko ga suki desu" because the "watakushi wa" was implied.
The trick for wa/ga is often just to remember that subjects are often implied in Japanese and missing from the actual text/speech. So, "Nekko ga suki desu" because the "watakushi wa" was implied.