I would try the 7mm WSM. Here's a hint for reloading: pay attention to the new Sierra reloading manual, and if you have questions, contact a guy named Paul Box.
He is a Ballistics Tech there, and has developed the loads for the 7mm. I have used other loads in the 25-06 and 30-06 that he developed, and they have all been on the money. My development time, when using his data, is next to nothing. I can guarantee that a 140 gr. BTSP or a 160 gr. HPBT will be more than adequate for deer or elk, respectively.
The other source for load development I would use is the Hornady manual. If you want a "tougher" bullet for the 140 gr., use their 7mm 140 gr. Interbond. Load development is longer, but I haven't seen a major difference in accuracy between the Sierra and Hornady products once load development is worked out.
I don't think that you could go wrong with either a 7mm WSM or a .270 Win. - but I would lean towards the 7mm WSM.