there is a big jump from a 30-06 to a 300win mag , there is almost no jump from a 308win to a 30-06 unless you go to a 200+gr bullet , and it that case you need a bigger gun
An often repeated fallacy.
Top loads from Hogdon's load data (sticking with standard construction bullets):
165gr bullets
.308: 2839 fps
30-06: 2972 fps
300 WM: 3144 fps
Velocity gain going from .308 to 30-06: 133 fps (4.7%)
Velocity gain going from 30-06 to 300 WM: 172 fps (5.8%)
180 gr bullets
.308: 2683 fps
30-06: 2840 fps
300 WM: 3042 fps
Velocity gain going from .308 to 30-06: 157 fps (5.9%)
Velocity gain going from 30-06 to 300 WM: 202 fps (7.1%)
The difference between .308 and 30-06 is only slightly less than the difference between 30-06 and 300 WM, hardly what one could call "almost no jump" versus "a big jump".
For a bolt action hunting rifle, the only compelling reason I've ever seen to choose the .308 over the 30-06 is lower recoil, which is to be expected in a less powerful round. Rifle weight? Both cartridges can be had in rifles that are light enough to be uncomfortable to shoot. Bolt throw? I've never felt particularly strained by the extra .5" of bolt throw on a long action. If you don't reload, i guess cost could be a minor factor, but if you do, or if you practice with the load you plan to hunt with, it's a wash.
If you don't think you need the extra power between a .308 and a 30-06, that is fine, but that doesn't mean it isn't there.
To the OP, if you want a 30-06, go ahead and get one, it's certainly one of the most versatile calibers out there.