Since you guys have finished with all of the grammar points that you planned previously from the book I assume you will start working on other grammar that is not part of the books?
In which case here is a convenient list of things that I found in the wild while reading books that you might want to include in BP.
I will keep updating this list as I see more stuff.
Stuff that you definitely need:
- あり (opposite of なし)
- あっと
- と言うのも
- verb+がいい
- ずく (relying entirely on)
- 僅か
- you have というわけではない but not と言う訳だ
- おおよそ
- ~ざる (i.e. ならざる, 見えざる)
- ~まんま~
- ならともかく
- となると
Stuff that you might want:
- とけ (short imperative form of ておく)
- なさそう
- なかろう
EDIT (05 Feb 2020) - a few more grammar points you need:
- いずれも
- ~ごとく
- がん~ (e.g. がん見)
- ~っぷり
- ~やがる (e.g. しやがる)
- ~振り (e.g. 無茶振り)
- それまで
- ~めく
- およそ
EDIT (22 Apr 2020) - a few more grammar points you need:
- 気もする
- むず
- やや~
- すら
- あわよくば
- なりに
- なにやら (you have どうやら, but no なにやら yet)
- どうにか
- ことで (example: 彼の入院は急なことで、みんな驚いた。)
EDIT (29 March 2021) - a few more grammar points you need:
- 多少なりとも
- とは (I think this needs to be a separate grammar point because it is used as a consistent separate construction)
- ~たりして (as an ending for sentences)
- ~ぞう (everyone knows this, but what does it actually mean? you can encounter it not just in anime, but even teachers use this at school as I found out)
- ~できて (sentence ending)
- ~にされると~
- より~ “more/even more” adverb (e.g. “より虚しい…”)
- 次第に (you have 次第で, but it is a completely different grammar point)
- 訳あって~