Maybe 10 points instead of 5 would work to kind of balance this. If Kreug and Dlfy are cool with this, we can change thisl.
On thing I do want to point out is the Center plants are HOMEWORLDs and the assults are going to be brutal.
I think 10 points wouldn't change a thing, although it is some better, especially with homeworld assaults figured in. I still think 20 would be fine and still make the center planets the main target, not just because of the points for one, but becuse they serve as resupply for the others, something not so much the case in enemy space. In enemy space the foe starts out with control of all the surrounding hexes so the work is doubled right off the bat, if not tripled. Puptting the total at 20 would not change the main emphasis, it would just add possible side actions.
I mean come on would you make a main emphasis on taking a planet that was just 3-5 hexes away from the next target through neutral space, or go after a planet thats next closest target was 7-15 hexes away in enemy territory? Even at the same point value, the main action is already determined.
I think 20 is the answer, 15 might work however, though I'm still skeptical.