"The engine is tuned for low end grunt"
I would have to argue with you on that one. I found the torque to be very lacking with my N1K, but I own a V-twin, parallel twin, and an opposed twin, and all three make better torque, and have MORE low end grunt than the N1K. Embarrassing when a Hardley can take you off the line the first 30 feet.
That being said, at 61 yrs old, nobody has said anything to me about why I own so many big cc bikes. (the ninja was a downsizing for me)
I have pretty much one of every style of bike, a cruiser, a supersport, an adventure bike, a supermoto, touring, and finally a great sport touring bike. All of which are at least 1200cc or more.
Oh, I also have a 650cc dirt bike, i guess that's a mini bike, lol.
I love everything about riding, especially hanging it out in the curves. I push all my bikes hard, and expect them to handle whatever I do. If a bike doesn't keep me happy, it's gone.
What you ride is your choice, regardless of it's size, style, or what anyone else may think.
If a 500 feels good to you, and puts a grin on your face, than that's the bike for you.
If a 1000 puts a bigger grin on your face, heck, go and get one.
You are saving money with your choice of a liter bike, and hopefully it pushes the right buttons and makes you smile every time you ride it. If that is the case, don't worry, be happy.
Ride more, ride to lean...