"This next one includes a whole planet."
There are systems out there with Partial planets?
Or are we talking as opposed to asteroid belts.
Personally, I would think that a planet would be easier to deal with than an Asteroid belt that has a decent level of industrialization.
No plan survives contact with reality...
Plans are plans. Combat is... Well, I'd like to have her as my captain. I just hope that "dealing with a planet" does not involves impactors. Retaliation is not a good thing.