i don’t know what your weather conditions are like, but i think hill sprints would help you with your start and drive phase mechanics. short sprints on a steep hill would force you to keep your foot low and push back with it.
compare your start here with asafa powell’s. in your first three steps you can already see your heel kick your butt and cycle around your knee. asafa’s foot drives straight forward below the knee which puts in him position to push back on the track and move forward. you also need that exaggerated arm action to get complete extension off the back leg. his mechanics, along with his strength, allow him to hold his drive phase for so long and get to top speed later than the field. i think if you did a steep hill workout focusing on these things you will feel the difference when you get in the blocks.