* Crystal Orb from PHB3 - a lot of will attacks and phsycic powers;
* Resplendent gloves for some extra damage
* Orb of Imposition class feature and daily powers that apply save-ends effects (don't forget Spell Focus feat on lvl 11). -8 to first save and -2 to all the rest can really lock the solo/elite-monster out of the fight
* Area attacks and Enlarge Spell feat. Crowd control for the masses.
All the rest is dependent on your party. For example: we needed extra healing so I multi-classed into cleric. In paragon this means you get a surge+3d6 healing for minor action (once a day). That is pretty neat.
And spread the Daily powers, so that you can have a variety depending on situation. Remember, you get to pick 2 powers and each day you choose one of them.
If you have the leader grant you THP - BloodMage becomes a nice combo.
To summarize: the wizard gets to be anything you want. Though not top-notch striker or top-notch defender, you could even fill those roles occasionally.