Here is a look at a Hybrid Swordmage/Wizard (one of the better hybrid combinations); I haven't built it how I would build my own character, I've tried to give it more of a more Blaster/Defender as you mentioned she was more of a Striker. Hence all the Fire Blaster powers. You could change STR for CON and take Aegis of Assault instead of Aegis of Shielding and take the Geneasi feat that adds STR to your elemental attacks to go even further down the striker line (but I prefer shielding swordmages ...)
Anyway:
====== Created Using Wizards of the Coast D&D Character Builder ======
Shielding Swordmage, level 11
Genasi, Wizard|Swordmage, Arcane Wayfarer: Basically for the mobility powers to get you in and out of combat more easily
Swordmage Aegis (Hybrid): Aegis of Shielding
Hybrid Talent: Swordmage Warding
Versatile Expertise: Versatile Expertise (Heavy Blade)
Versatile Expertise: Versatile Expertise (Light Blade)
Elemental Manifestation: Windsoul: You can fly, yay!
Background: Arcane Refugee (+2 to Arcana)
FINAL ABILITY SCORES
Str 10, Con 21, Dex 11, Int 21, Wis 14, Cha 11.
STARTING ABILITY SCORES
Str 9, Con 16, Dex 10, Int 16, Wis 13, Cha 10.
AC: 26 Fort: 22 Reflex: 22 Will: 22
HP: 83 Surges: 12 Surge Value: 20
TRAINED SKILLS
Endurance +17, Athletics +10, Arcana +17
UNTRAINED SKILLS
Acrobatics +5, Bluff +5, Diplomacy +5, Dungeoneering +7, Heal +7, History +10, Insight +7, Intimidate +5, Nature +9, Perception +7, Religion +10, Stealth +5, Streetwise +5, Thievery +5
FEATS
Level 1: Hybrid Talent
Level 2: White Lotus Riposte
Level 4: Intelligent Blademaster
Level 6: Arcane Familiar: Dragonling to deliver one of you Blast Powers (Burning Hands)
Level 8: Versatile Expertise
Level 10: Burn Everything: Alot of powers chosen are Fire Attacks, so this is important to have to get by creatures fire resistence
Level 11: Double Aegis
POWERS
Hybrid at-will 1: Booming Blade
Hybrid at-will 1: Freezing Burst
Hybrid encounter 1: Burning Hands
Hybrid daily 1: Fountain of Flame: Big Damge Daily
Hybrid utility 2: Channeling Shield: Great Defensive power to have when your DM won't violate your Mark and even boosts your damage.
Hybrid encounter 3: Dimensional Vortex: Move an enemy around the battlefield and make them attack one of their allies instead of your ally
Hybrid daily 5: Swordmage Shielding Fire: Awesome power that lets you have two people marked with your Aegis all encounter long and dish out damage when you reduce damage
Hybrid utility 6: Wizard's Escape: Interrupt an attack that hit you and teleport away to wherever best suits you. Brilliant for a Swordmage.
Hybrid encounter 7: Fire Sea Travel: Damage all next to you, half blind them and teleport away.
Hybrid daily 9: Summon Succubus: Okay, I know ... this totally doesn't fit ... but I'm sure your player will have a lot of fun with this awesome power! Dominate them!
Hybrid utility 10: Dimensional Dodge: Interrupt that lets you get up in the face of an enemy suddenly attacking from a distance.
ITEMS
Melegaunt's Darkblade Longsword +3: Scores crits on 19-20 which will trigger your paragon path power Teleport more often, The Raven Queen's Shroud (level 3), Siberys Shard of the Mage (heroic tier), Lightning Longsword +2: Back up to change dmage to Lightning if you are fighting creatures immune to fire or with massively high resistence, Githweave Armor of Aegis Expansion +3: Cool encounter power that enhances your Shielding Feature, Raven Cloak +2