VCT--while this may be a minority view here with the TurboBusaBarfers--the majority of really good riders start off on very small displacement bikes. They do this because learning how to be a good rider on a large displacement bike throws extra challenges at the rider that in most cases are never over come.
The reason for this is on the bigger bikes the important experimentation needed to develop the skills are overshadowed by the risks, which trigger survival instincts that block the learning pathways. That said the human is an incredibly adaptable animal which can over come much adversity. Now ask yourself this question--do you really want to put extra adversity in the path of your learning to became a competent rider?
For all that it is the Ninja 250 is way too much bike for a beginner. Even seasoned riders have been mortally put down by that bike. It is too heavy, and has too much power for a new rider to get the most out of their learning--the new Honda CBR250 isn't a better choice for it basically suffers in the same ways.
When you hear people talking about a bike not being large enough for the freeway that should be an instant clue that they are talking about a stage beyond a first bike. If the bike is capable of being a decent freeway bike then it is too much bike for a new rider. It will be too heavy and too powerful for the new rider to properly develop the needed skill set. Additionally, due to the overwhelmingly fatal nature of a mistake on the freeway the risks involved with riding on the freeway before developing the necessary skill and judgment needed to survive on the freeway out weight the benefits of freeway riding. Simply put stay off the freeway while you are developing competency on the motorcycle.
Cruser bikes while useful for exploring a life style suffer a mechanical disadvantage for learning how to ride. They place the feet too far forward to allow the rider to learn important riding techniques, and therefore make for a poor choice for a first bike.