Does your bass line use a lot of rotation in its stroke? Sometimes -- like when playing Flam I Am -- it looks like your right wrist might be using a whole lot of rotation for your upstroke instead of bending or hinging vertically.
Like drumicide mentioned, you've also got some "ashtray hand" going on. The palm of your hand should be more vertical -- not like a pure vertical 90°, but something like 60°. To use your rain water analogy, you're catching it (or coming close) and you shouldn't be.
Another thing to watch is your tap/accent definition. When playing Flam I Am or anything with distinct taps and accents, you should have two
defined heights -- not only do your your accents need to be at a defined height, but the taps need to be, too. If you watch that video clip, you'll see that your non-accented notes vary pretty widely in height. Some are a few inches off the pad, while others are almost as high as your accents. Use a single hand two-height exercise (Bucks, Thirteen,
8 and 4 from SnareScience, etc.) to work on your heights. Accents should be nice and strong (which you also need a little work on), but taps should be low
and consistent.
Overall, though... Good start! Keep it up and have fun!