i sometimes think the world is out to get me...
but we're all in the same boat and we learn here and over at geep's place and wherever else.  you just gotta be patient and do every tut you come across.
i've been working on animation too, but just cyclic stuff for now.
if you're having to add keys to the parts you don't want to move, you may be getting overshoot from the spline.  try to use linear splines when you can.  you can key originally curved, then mark a few spots on the curve and switch to linear and get more control.
o and that inverse kinematics is good to get going but might be better off trashed as you approach the final animation, cause ik rekeys every time the animation is run, so it'll always look different and throw issues.  (i understand character studio keys one way and keeps it, but i haven't used it) really messes up cloth dynamics too, so if you're going that route don't even run the cloth 'till ik is off and off for good.  turn it on once, new keys everywhere.
geep had a nice description of the splines working.

i don't know how to pull off the shaking hands easily.  i tried that once by reparenting the hand.  that was not successful.  i would just say at this point that's gonna be one of those "key every other frame" deals.

#7 sounds pretty easy.  you can just use break spline as you switch from one maneuver to another to keep overshoot down and animate in chunks.

trying to render quality animation for us is still yucky when a single frame can take several minutes to many more.  you gotta compromise there.  if you go toonish  you can render much faster.  if you're going for realism, better get the renderfarm.

o yeah and for #2 the easiest way to do that is to open the splines and just delete mucho frames from the animation, anything that is not a peak, lull, or zero.  then you can tweak it from there with much less stuff in the way.  but be careful...again, if you have curved splines, you'll get crazy new overshoots, so go linear at this point again. before deleting splines

go that way really fast.
if something gets in your way
turn