The key with EKs is you are using magic to increase your defense not your offense. You have a few offensive spells that are useful without multiclassing into a wizard. I suggest 3 builds for the EK.
The "Death Knight"
6 levels of fighter with EK + 6 levels of Wizard (necromancy) This gives you all of the buffs for being a necro wizard and 3 feats along with major bonuses for being a fighter.
or
PURE EK 12 levels of fighter.
or the EK+ build
11 fighter + 1 Wizard to scribe spells.
