Here’s my opinion on the “want to move up from a 250” statement. If were talking about a Ninja here and not a cruiser, then I don’t buy it. Will there come a time when you wish you had more power to overtake someone? Sure. Will there come a time in the twisties where you wish you had more power? No.
I have a very heavy 500cc maxi-scoot (less power to weight than the Ninja 250) and have done 26000 miles in little over 2 years. Do I wish I had more power now? Yes, but when it comes down it it’s only on very specific occasions. I’m having most fun when leaned over into corners on twisty country roads. I am not at full throttle at those moments so why do I need more power? I don’t. Sure it would make my life easier when I come up behind a slow car to have instant acceleration on tap, but that power would probably have got me in trouble in the early days. Do I regret buying this as a first bike? Not at all. Most of my riding buddies are on 1000cc+ cruisers and have been riding for a lot more years than me but that cannot stay with me in the twisties. That says a lot more about them than me but you get my point. Don’t get sucked into the whole power thing, especially when you are brand new to it. Trust me, you will have plenty fun on a 250 (especially when you smoke folks on larger bikes )