Re: trying to improve distance and form
Your overall mechanics are good, especially letting line shoot through.
I concur with Frank. While wrist action is needed, yours is a little too floppy.
Again, echoing Frank and others, you have way too much slack line out.
A concept that really works for me is is to concentrate on accelerating through both the backstroke and forward stroke.
Now here's the zen of the whole thing: let your wrist snap forward at the end of the downstroke while letting the line run through your hands and subsequently the guides.
...This is impossible to describe in words.
...Just youtube it.