You may say that the size is just right, but trust me, when you have the baby with you in a proper baby seat and the stroller and baby stuff in the back (bottles, diapers, sterilizer, etcetera), you'll realize some of these "compact" European crossovers are not just compact... they're cramped. You'll get better space out of a plain-jane CRV or a "compact" car.
For wifey and kid, I wouldn't suggest an X3... though I don't know if the current one rides as badly as the old one, the old X3 was one of the most uncomfortable vehicles I've ever driven.
If it's a car you're going to drive yourself, but will need to cart around baby stuff in, stick to a midsizer. Of your original choices, the Q5 will most likely do.
No idea about the Evoque, but it's bound to be a long ways down the line. You might want to look at the Range Rover Sport, it's a great looking, great driving car, not too big, but with great room inside.
The Q7/Cayenne cars are rather on the large side... though the Cayenne doesn't feel that big to drive. The X5 is just right in terms of in-city manageability. The X6 is silly, but damn is it a hoot to drive... has great trunk space, too.

You can get your sportscar and family car all-in-one with the X6.
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Down the rungs, the RX-series is big enough, but just lacks in the "posh" area compared to the Europeans... though the RX-hybrid is very comfortable, very entertaining and very frugal. Still, the extra you pay for the hybrid model isn't reflected in the interior materials. The Volvo XC60 gives you much of what a Q5 or GLK has to offer for much less money, and is available in diesel. Still not quite up to Audi interior quality, but a little better than an RX.
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If you're willing to go lower, there are some excellent Japanese/Korean vehicles in the sub-3m range. The CX9 has always been a favorite of mine. It's large, but it drives like a much smaller car. And it's got the "bling" and exclusivity factor plus a kick-ass V6.
The current Pajero is very car-like in the way it drives, and it's available in diesel, to boot.
The Murano is the most compact of this group, but rear seat space is good, the ride is great, the transmission is smooth and interior quality is surprisingly nice for a Nissan. (comparable even to the Lexus RX, I'd say)
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Don't limit your choices to the usual. Shop around. There are many cars that may surprise you. You may find that you can get BOTH what you want and what you need from something with a surprisingly small price tag compared to what you're looking at.