I personally think the N1k is a "do it all" bike. People track it, I tour it and twisty it. I'm getting old and my SPORT touring is turning into Sport Touring but for my local favorite roads the bags are off. Longer trips (no freeways, TYVM) the bags often get dropped at the motel (campsite) and local favorite roads get the "bagless" treatment. Not that the bags really get in the way but in the twisties, you will feel the extra weight. My Ninja gets used for long tours, short tours, local errands, lunch 100+ miles away. It would be a daily commuter but I'm retired.The sv650 is very versatile so I want my new bike to offer me things that the sv can’t. Do you think owning the sv650 and a ninja 1000 may be redundant?
That said, keeping two bikes is really up to you. I'm not sure about now but 10-15 years ago there was a huge SV650 contingent that raced these bikes. Way cheaper/simpler to do than with a literbike and the SV is a bike someone can really push the limits on. Most literbikes (N1k included) have limits so far out we aren't really testing them -or- if we are testing them, especially on the road, we're seconds away from being way over our capabilities. (speaking for myself) I'm not one keeping something just for the sake of having it. If I was, there would be a well used 1998 VFR sitting beside the Ninja in the garage. But others have amazing collections of bikes. Some switch off riding all of them. Lots of reasons to collect anything. What do YOU think?
One further thought...keep them both. A year from now see if one is covered with dust and maybe decide it can find a home elsewhere. Or are you thinking "I rode that one a couple days. I really wanna ride the other one to..."