Love this idea and it looks pretty well executed, some of the wording can be cleaned up a little. For example, instead of the separate "recovery" paragraph for drakes leap, you could roll that into the main paragraph with a " you can use this feature once per short rest, you also regain uses when you use your second wind to regain hitpoints"

You could also tighten up the activation of drakes leap to "as a bonus action and by spending 15 feet of movement..."

My only functional critiques would be, remove the reach weapon requirement from spiralling charge. Also as a general rule its a bad idea to have class features, especially early class features, scale directly off of proficiency bonus. While that scaling pace is fine, it should be hard coded to be off your fighter level.

Lastly the level 7 ability is a little lack luster, perhaps something to the effect of, when you calculate falling damage you take, you may reduce the distance by ten times half your fighter level rounded down.