Congrats for that fastest KM!!!!
Remember, every time you do interval workout to start slower and do the next repetition if not equal, slightly faster, but slightly!!!! Don't kill yourself
That cadence is impressive! Too much I would say... the perfect number of steps is between 180/190. Try to smoothly enlarge your stride and automatically your cadence will be at that number (It is not easy, it is a question of practice and many Kms) so your Running economy will improve, with less cadence yo will run the same pace, catch it? less cadence means lower energy but higher impact, since you change a little your kinematics...
Next long run try to maintain the cadence below the obtained.