You can skip over Dead Asteroids, since they only cost resources...
I tried skipping planets once, but they ALWAYS find the weakest point and set up camp (once I had 50 planets, upgraded everything and they STILL found the one unfortified planet deep in my territory...
Oh, If you play the Starwars Mod, and you are the ONLY Empire fleet, you can take over the entire galaxy from just your home planet (just station a couple star-destroyers by each homeworld and "Execute Order 66", and invade all the enemy homeworlds simultaneously

I learned that they ALWAYS (when they have them), send siege frigates to a neighboring planet as an immediate counterstrike when you invade their homeworld...