And a fine nic it is 06. The Holland is a bit like the .44 Magnum if you're a handloader. They can be loaded up or down to suit the user. I have a load that almost perfectly duplicates the 30-06 trajectory (165 gr.) with a 235gr. Speer soft point, and I used it for a coupled of years for deer hunting to good effect. The only reason I stopped was because the rifle was too heavy in the mountains, and I hate to neglect my other rifles. I'm not particularly recoil sensitive but one can't argue that a full house Holland can jump. I tried to shoot one of mine from prone position once, and I was worthless after about 5 rounds. It plain hurt.
If I had to pare back to one rifle (unthinkable as that is) I'd go with my Winchester M70 chambered for 30-06.
It’s been a looong time, but I rather liked the .375H&H magnum. More recoil, than a .416 Rigby, but handleable. I did try .458 Win and .460 Weatherby magnums, but they were a bit much. I could use one if I needed to, but I can’t say it would be very pleasant.