The problem with a jump from the 300 to the 1000 is that you may find that the 1000 is too much (both in cost and power) and going back isn't all that easy. Buying one without having ridden one is a very risky financial-investment. KNOW what you're buying!

This goes for any bike, but more so for more-expensive supersports and literbikes.
If you can, try the bike out first...through a friend, a rental, etc. Ride *some* kind of literbike before diving-in. Why? You may realize that you'd be fine with a supersport, or one of those larger-engine middleweights such as the Ninja 636 or Daytona 675(R).
I think the 636 would be a better choice, and you pretty much just don't need a literbike on the street, though the power is fun (I owned an R1 for a couple years).
Literbikes are easy to ride slowly but yes, they will go FAST. Way faster than you can think if you decide to grab a fistful of throttle.. Even an experienced rider has to acclimate to a faster bike or it will overwhelm not just your skill, but how fast you can think. If you're used to thinking at a certain speed on a slower bike, then you will need to think faster on a faster bike...so don't ride faster than your CPU (your brain) can process the information coming at it (road, turns, conditions, etc.).
Really, it comes down to throttle-control. A lot of people make them sound worse than they are, but a lot of people give advice without ever having-ridden the bike in-question, or any literbike for that matter. In my view, people who haven't ridden a supersport or literbike shouldn't give advice for or against these bikes....though they may know technical information about them.
Literbikes are just machines with more potential power. My 300 will get me in trouble if I use too much throttle in a given-situation, and literbikes are no different. Want less power? Use less throttle. It sounds glib, but it *really* is that simple.
Now, in comparison, the literbike will feel like a rocket *if* someone is foolish enough to hop on and ride a literbike like a 300, but who's that foolish? When I owned my R1 and my Gixxer 600, the 600 felt downright SLOW. Why? I was used to my R1. If I rode a Gixxer 6 today, I am sure it'd feel quite fast compared to my experience on the 300. That's why when we try new bikes (even our own new bikes), it's important to adapt. Some people adapt faster than others.
A lot of what you feel on a bike is relative to what you already know (or don't know), but if you have any kind of respect for the machine and any kind of common-sense, you can ride a literbike as easily as a 300, given that you're willing to learn the machine and adapt to it.
Remember, the real trick is your software—your brain. Bikes are machines and they do what we tell them to do.
Here's a video where I swapped bikes with a local rider/racer, SuperBikeShaun. His bike is a heavily-modified Gixxer 1000 and he got to ride my nicely-modded 300!