Congratulations, and good advanced planning. I'll recommend performance station wagons as the best solution. You'll need the trunk space, and if garage depth is not an issue (or can be fixed), you might as well.

I second Bitt's recommendation for Volvo, but my 2000 V70 (wagon) has had far less problems in 50k miles (its second 50k miles, I bought it used). And yes, the dealerships are terrible, so find the local Volvo guru mechanic (by asking neighbors who have them) and take it to him instead. Might as well get an R to satisfy the need for speed, and if you try real hard, you might be able to get one in manual.

Then there's Dodge Magnum. All the practicality that your wife wants with all the power that you want. No, not manual (which is why I don't have one), but you can't complain about the ~320HP (?) under the hood. It's apparently built like a Mercedes, so hopefully it can be trusted.

I'll also second genixia's Mazda6 Sports Wagon. I don't know much about it, but it's got that power/practicality thing again.

And I couldn't go without seconding TigerJimmy's Benz E320 recommendation. If you don't mind buying used, this would be the one. And if you're adventerous like me, you might just call Germany and see how much it would cost to import a (used?) one with a manual.

Good luck and keep us posted!