Be careful with a pull buoy- they can be like crack for triathletes. As said, they can turn into crutches and mask body balance/position flaws. Also, go easy when you first start to use one because they can load up your shoulders more than you think (you turn off any kick propulsion, you then try to hold your lap time with pull alone, you get more strain on the shoulder)>
The best thing to do IMHO is to try to develop a sustainable two-beat kick that helps you with balance and rotation but doesn’t such the oxygen out of your blood so fast that you go anaerobic. Search YouTube for two-beat kick vids and read some descriptions then practice. Once mastered, you’ll only go to a turbo kick to bridge to a swim pack, pass a floundering yahoo, or hit the exit chute first.
Two beat kick; you heard it here first.