🚀 go-pugleaf

The source of thrust to move the planet doesn't have to be placed on 
the surface.  Consider moving an asteroid into orbit around Venus and then
stopping the orbit and using thrusters to "hover" the asteroid over the
surface.  The gravitational pull will act as a "tractor beam" to pull on
the planet.  Use a big asteroid and put it as close to the planet as
your thrust system can tolerate.

On the subject of force.  The most energy efficient mechanism is hooking
into something substantial and pulling, examples include cars, feet, and
aircraft (to a lesser extent).  The least efficent mechanism is throwing
low mass at high velocities (light is the ultimate example).  Of course,
efficiency is somewhat relative.  Conserving reaction mass is often a 
goal, in which case, throwing light out the back is the best, and particles
at nearly the speed of light is also quite good.

jeff millar, millar@mervax.sanders.lockheed.com
--
Jeff Millar Lockheed Sanders, Inc 603-885-7047
These are my words, not my employers, etc, etc, etc.