These are good questions. You probabably already know that a poor kick start is much slower than no kick start at all, so I think you are smart to focus elsewhere in the interm.
The first thing about a good race start is pure animal psychology. There can be no doubts, fears - its focused aggression. Explode out of the start!
As far as the skating, unless the first gate has been put in a bizarre location by the course-setter - there is usually always advantage to one or two powerful pushes.
The trick here is to push hard and fast onto a totally flat ski (or as flat as possible considering the line you must take). Also people have a tendacy to slightly 'overpush' - the last tiny bit of their extension acting to slow them down because it is no longer thrusting but just hanging out there.
In addition, something that seems small but when racing for 100ths of seconds can be big. When you pull a ski back into parallel after pushing off of it - you want to present as small of a wind cross-section as possible. If you pull it back around with the topskin really pointing in your direction of travel you've somewhat decreased your aerodynamics.
Also, once you have given one or two strong skates - you usually will be already traveling at a velocity which exceeds your explosive leg velocity . . . ie you'll be slowing yourself down by trying to skate anymore. Get as aerodynamic as possible for the situation/turns coming up and tear the course up!