Evoker
Overcome resistance: once per day + one extra time per day every 2 levels beyond 1st, a spell cast by the evoker partially ignores a target's resistance to the spell's energy type (the resistance is treated as 10 points lower).
Cost: an evoker with this feature doesn't get bonus spell slots from specialization.
Energy Sustitution: once per day every 5 levels, the evoker can freely change one spell that has an energy type (fire, cold ,electricity, acid, sonic) to any other energy type.
Cost: the wizard bonus feats at levels multiples of 5.
Energy Affinity: +1 caster level on spells of one energy type of your choice.
Cost: familiar
Necromancer
Enhanced Undead: all undead created with your spells have +4 to Strength and Dexterity and +2 Hp per HD.
Cost: an evoker with this feature doesn't get bonus spell slots from specialization.
Undead Apotheosis: at level 5 you get +2 bonus to ST vs sleep, stun, paralysis, poison and disease; at level 10 you get +4 bonus to ST vs ability damage, ability drain and energy drain; at level 15 the bonus vs sleep, stun, paralysis, poison and disease increases to +4; at level 20 you get 20% resistance to critical hits.
Cost: the wizard bonus feats at levels multiples of 5.
Skeletal Minion: instead of the normal familiar, you have a human warrior skeleton companion with HD equal to your level (no special abilities like the familiar, but bonuses to Str, Dex, nat armor, and it doesn't cause Xp loss if destroyed).
Cost: familiar