[yuriyuri]

Originally Posted by Harumaki

いままで文法の間違いや変な言い方は使ったことがあり ません。

Just because I feel as though this needs to be pointed out:

Originally Posted by hatsuto11

貴方みたいに日本語で流暢になるのを楽しみにしてます！！

貴方 - Why the kanji? And why not use your name?
日本語で - Should it be 日本語が? (“fluent in”の検索結果（31 件）：英辞郎 on the Web：スペースアルク)
Why みたいに with a sentence ending in ます? surely this is an imbalance?

Don't worry, my post is not just to point these things out, but also to give useful links on the grammar the OP asked about:
てもいい - Expressing "must" or "have to" | Tae Kim's Guide to Learning Japanese
方がいい - Using 「方」 and 「よる」 | Tae Kim's Guide to Learning Japanese