RE: 30-06 or .300wsm
For deer the .270 and 30-06 are too close to see a real difference. The .300 WSM would be more of a step up in performance. Personally though, since you already have a fine cartridge for open areas, I would look at brush type or close quarters gun like a 45-70 lever gun or the new/old Remington 673 in 350 Rem. Mag.