You mentioned being able to upgrage the video card. There are few laptops that have an official upgradable video card and they are usually very large and expensive with short battery life. I'm not sure if Dell sells upgrade modules for the 9300, which may be a good option.
IMO it isn't worth worrying about an upgradable video as it's primarily a gaming concern and by the time you 'need' a new video card, the rest of the hardware is outdated anyway. I personally looked for something from a go 6600 or X700 and better.
You also mentioned you wanted battery life that doesn't finish fast. How long a battery life do you need? The better the laptop is at gaming, the shorter the battery life. If you provided yor minimum time it could help people identify options.
I have a Toshiba M40 JM3. Their models vary per country, mine was $1900 cdn. It has a go 6600, that works well for my gaming. Only a 15 inch screen though. I get around 3 hours battery on low power. it is 6 lbs.