Hello, and good morning/noon/evening, hojicha. Great job on your quicker gesture drawings for 2 minutes and 30 seconds. Way to go, please keep it up.
My tiny, littlest suggestion is that you're using lines that are way too choppiest with too much use of your wrist. Would you like to go for 10 minutes of 29 second drawings, (about 21 drawings) using your elbow and shoulder? The reason is because your lines will become smoother and the most confident. For more details, be sure to look at the Proko videos on gesture drawings. So check this out.
Hope this helps, supports and benefits you and me.