I'd recommend a Ducati Monster 620 Dark, circa 2004 - 2006. It offers an incredibly wide torque curve so traffic isn't a chore, very low center of gravity saddle, relatively upright riding position, naked bike for more interest at lower speeds, and a very easy but engaging ride. All this in a package that won't "eat your soul", but instead offers classic beautiful Italian machine lines. Price is right too.

That said, I now ride an MV Agusta F4 Brutale, which seems to offer sport bike performance without the soul eating. There's never, ever, an urge to ride wheelies downtown to show off your uber Ninja neon green decals.