I play a a lot of assassin. And I really wish there were a way to make it so holding shift enabled my sprint and releasing it disabled it. I am used to this scheme from many other shooters and I am sure there are many other gamers out there who are too a bit perplexed by the toggle sprint as it is. Just a simple option would help. I tried messing around with the input.ini by adding "| onrelease Useskill1" to my bind commands but it didn't work
If it helps, I play just by doing as you described. I hold down my shift for sprint. I do realize that it activates on toggle, but it doesn't seem much different to me if I pretend to hold it down. However, in order to stop dashing you have to stop moving and that's something I don't think you can fix. Also, I would like to say that I would like something like this implemented if possible because assaults fly skill kinda bothers me as toggle. Sometimes with lag it just doesn't activate/deactivate at certain times and it can be confusing.
Yeah I've had instances where I merely intended to jump again and ended up floating just above the ground. Worse is when you try to stall for half a second in mid air to jitter a sniper's aim and end up floating flatly, easy headshot material.
Maybe instead of a toggle they could had a modifier key, like holding ctrl then pressing E would upgrade my charge as an assault, etc. Just a thought.