I think I see what you're getting at.
Caution: the role of controller is cool. Striker is very different. Sorcerer is a bit awesome (which is why I play one) but keep in mind that you don't have to tag more damage dice to the wizard to make it the most powerful. Whatever challenges you put in front of them (and get creative here, it's not just cookie-cutter for any adventure), tailor them to the strengths of whoever is playing.
But, you want all the heroes to be heroes. Don't make it boring for everyone else, whatever you do. I know I hate the background; I like the spotlight. If I wanted to be a swordmage rather than a wizard... I wouldn't want to sit by while some player hogs the attention. It's a sign of bad GMing; really really bad bad bad bad bad GMing. I've suffered through nights where that happened, and if this could even remotely resemble your hopes for the scenario you describe, you should be very wary of that while you do this.
Basically you can statistically change them, or simply save yourself the math and design encounters with the Wizard in mind. My below suggestions are a bit of both. I recommend the latter option (making the adventure with them in mind) as it's easier to make them shine than hope that stat changes will do it for you.
MORE MINIONS: wizards are designed to annihilate minions. In Turtledome! (living 4e, here on the boards), I'm playing a sorcerer who used to be a wizard; we picked an arena battle vs. 100 skeleton minions. At the time, as a wizard, it would be a piece of cake to fight 100 minions (we had 2 wizards). Then I got morphed by a demiplane, and sorcerified.
What I'm getting at is that the wizard will seem more powerful if he's nailing 9 minions with one shot, which a sorcerer or warlock simply cannot accomplish. Scorching Burst, a Wizard at-will, can take out 9 monsters in one shot. Wow, that can be powerful.
Then throw in a solo brute to let the warlock, sorcerer and swordmage shine a bit. These guys do better with lots of damage on one target.
HYBRID PCS: what if the wizard is a hybrid druid? they can have a wolf form as a backup to their regular wizard abilities.
OTHER CONTROLLER POWERS: Are you using the Druid? You could allow wizards to use Druid and Invoker abilities, judging on a case-by-case basis. Decide what fits how you want wizards to be, then do it.
OTHER ARCANE POWERS: let the wizard use Swordmage powers, or sorcerer powers using Int rather than Cha. This is a bad idea, I'm warning you now, but you sound like you might want to do it.
MORE USE OUT OF CANTRIPS: make up scenarios where a Cantrip would come in handy. Not the only thing, like one answer for a riddle, but where it would be helpful. Specifically mage hand comes to mind. Imagine a SPHERE OF ANNIHILATION that can only be directed by Mage Hand. The sphere has to be moved into place, or contained in an item the party has, or the universe will get blown up. The other PCs can fight Orcus, or whoever. The Wizards can aid each other moving the sphere as minor actions (or move actions) while using ranged powers to attack in the same round.
TEACH THE PLAYERS HOW TO USE WIZARDS PROPERLY: um, yeah. They need to think outside the box with wizards.
