Keep the 243 because its your most accurate, or sell it if you need the money.
Keep the 30-06 because its your most sentimental.
Buy an all-weather 30-06 in a platform that you really like, and hunt that till you die. Use your original 30-06 when you want a little nostalgia. You should always have a matching redundant backup hunting rifle ready to go in the same main chambering that you run. You can't beat a couple 30-06 for that purpose.
