either one will work just fine. I use a 7mm rem mag for antelope to moose and never needed more. I have shot 6 bull elk with a 7mm rem mag and not one required a second shot. I have also shot elk with 300, 270 win and bowwhich also did the job just fine.I contemplated the 300 wm yet again a few years back but stuck with the 7mm rem mag as my all arounderfor my usage, saw no real life advantages to it for my sitaution and the rem mag has done everything I have asked. If I needed bigger my start point would be the 338wm.

As mentioned not a great jump between the 3006 you currently have a 7mm rem mag, more so with the 300wm but if you plan on keeping/using ole trusty you may consider diversifing a little more. All the game you mentioned will fall to an 06' so it's not a need think as much as it is a want! So pick whichever you truly want.

Good Luck