When I write about tossing, "forward" means more toward the target Service Box. As a "six-footer, plus" you're toss placement can be farther "forward".... Yes, actually. (It's only a matter of "degree" but "Yes" the tall Topspinner is hitting slightly higher on the ball than the short Topspinner.)
Continental grip not "required", but definitely more helpful. As noted all over these boards, Boris Becker could hit all his serves with an Eastern FH grip(!).
Whether Flat, Slice, Twist or Topspin, the Continental grip is (generally) understood to make serving more effective. Many Servers prefer the Eastern Backhand for serves. I -- and a few of my peers -- use an extreme EB grip for all serves.
Wrist-snap. Boy! (You have no idea what a "powder keg" you just opened with that question...!)
The phrase "snap your wrist" causes so much grief on TW. My really *Anal* TW friends will argue ad infinitum that "wrist pronation" is so much more correct ... (and they are correct.) But "snap" is okay with me ... so long as you mean "pronate".
Now, to answer your question.... Yes. Once you've "loaded" your body for the serve, and are unloading your coiled body into the ball, yes, you snap your wrist to make your racket strike through/up/over the ball.
Are you back with me?
- KK