KMK薙刀式の変換時間

下のログはKMK薙刀式のかな変換時間（キータイプ時間を含む）です。 １キー単打、２キー同時なら問題ないと思いますが、３キー同時で100ms弱、4キー同時（ロールオーバー）だと300ms近くかかっており、 目に見えて遅い。 100ms以下には短縮したいと思っている。

ng_type 1-keys took 12 ms
ng_type 1-keys took 7 ms
ng_type 1-keys took 10 ms
ng_type 2-keys took 35 ms
ng_type 3-keys took 86 ms
ng_type 3-keys took 92 ms
ng_type 2-keys took 52 ms
ng_type 2-keys took 34 ms
ng_type 4-keys took 188 ms
ng_type 4-keys took 272 ms
ng_type 4-keys took 207 ms
ng_type 3-keys took 86 ms