Some good spear builds at this cap are;
90 fire/ice/heuksal - sub lightning. This balances out the spears weak defense and it packs a punch, the phy dmg increase also means that your high powered skill moves can rip through other int builds.
90 ice/lightning/heuksal - sub fire. This build gives you mobility that that other builds do not, you have teleport, grass walk and lion shouts, its based around speed and fast attacks, you also get a mag dmg increase from lightning that greatly increases your nukes attack power.
As for a force nuker or a mage, I would reckomend using s/s instead, the lack of weapon skills means that you need the shield for extra defense, but if you plan on taking force then I suggest also taking fire/ice for more defense. All of these builds I suggested are pure int, but they can be adapted to hybridize quite easily.
Hope I helped.
