It might be important to know if you plan to hunt anything larger than deer?

Although you mention the .270, you'll almost by necessity be forced into a standard-length action, rather than the short-action your present .243 is more likely than not based upon. Not surprisingly, you can expect the extra capability that comes in a .270 to also bring with it slightly more weight. Have you considered at all the .260, .7mm-08, or .308 at all? Any of those will likely allow you to stick with a lighter action.

Though I'm also a fan of the Model 700s great and small, I've also become a fan of the Weatherby Vanguard and its near-clone, the Howa 1500. In spite of its long-action, my Vanguard is an easy carry. If you can consider the aforementioned short-action calibers, a great compromise might be the Remington Model 7.

Most of us do just fine with a 3-9x. I haven't found many redeeming qualities in any optic I've found for less than $200, but in the same breath I've had three mid-range Leupolds (VX-2s) taking beatings on anything from .243s to .300 Weatherbys for a few years now and still hold zero. You many not get the use out of a VX-3, Swaro, or Zeiss to justify the premium prices you'll pay. Just buy the best glass (and mounts) that you can afford and you'll do well.