Learning kanji is very important! Kanji helps give meaning to words.
You will probably able to master hiragana and katakana pretty fast as there only 46 basic characters each. However, you will need to spend more time memorizing kanji as there are quite some number of them. There is no quick way to learn kanji. The key is to maintain learn them without stopping halfway.
If you can continue to learn them for at least a year, you will definitely notice difference comparing to the time before you start.