Weapon art qi essence control. That was what he wanted to improve on next. Just like how his casual fist had become strong, that was just how he wanted his weapon attack to be like. He didn't want to end depending on his sword intent in every tough situation as it seemed to abnormal for him to have sword intent at his current age.
And in the case he didn't want to be dependent on it too much, then he had to rely on what would be viewed as normal and this he decided to train on his qi. Qi control while using a weapon proved to be useful as an attack while using swirling wind technique without any essence couldn't be compared to the power of the same move when he used his qi.