RE: Second rifle choice?
Going up, 338WinMag or 375 H&H.
Going down, 243 or 25-06.
Space your cartridges out enough so as to make a real difference in killing power (up or down) and trajectory (up or down).
A 30-06 and a 7mmRemMag are essentially equivalent.
Some folks fill their closet with rifles that are essentially the same power.
Never fails to amaze me.
EKM