I would rate them in this order of priority:
I spend each war 1-2 attacks on taking outposts. Many of my team members just go for the uplinks and sometimes score just 1 or 2 uplinks. Those attacks are essentially wasted. Anything less than 3 uplinks is a failure imo.
So yes, outposts are extremely important. I like to let the enemy take Takodana/Dandoran first (which increases it to lvl 6), then I retake it. They take it back and I capture it again, raising it to lvl 9. And that's the moment lvl 7-8 players are having a lot of trouble to assault it. I have never lost a lvl 9 outpost yet. It's so funny to see "Player X is attacking the Heavy Munitions Plant!". Then silence...... for more than 2 minutes. Haha
Even hostile lvl 9-10 players don't take it back... I don't understand it. Maybe they are intimidated by that beautiful maxed lvl 9 base with a shiny droideka. Ah well.