Re: What Caliber and Rifle to buy?
Like Roininflag said, the rifle you choose will be a bigger factor in achieving satisfaction than the caliber.
That said, I would go with one of the 6.5's considering you already have a 7mm Rem Mag.
264 WM Sendero, 260 Rem 700 Mountain LSS, or perhaps 6.5x284 Savage LRH if you handload. same caliber, but 3 very different rifles
If you feel under-gunned for Elk, use the 7RM or get a big gun.