Keep your .270. It will do just fine. Don't think that your days of shooting long shots are over. There are plenty of times in the east when you can use a 400+ yd deer rifle - it just depends on where you are hunting. Lots of hunting in the eastern states is going to be on a stand overlooking a field or food plot. If you are sitting over a field that's 500 yds wide, then you could need a 500 yd gun.
Lots of us eastern hunters keep at least two deer rifles. My normal rifle of choice is a scoped 30-30. It's light, short, and with Hornady LeverEvolution rounds, I'm good out to close to 250 yds. However, if I know that I'm going to be using a stand overlooking one of the bigger cow pastures, I've also got a 30-06 and a .270.