For a varmit rifle, I'd take the 22-250. The 25-06 works great but I see it more as a hunting cartridge. You could make whatever you want into a varmit rifle, I used a 338 win mag years ago. It was a hoot but a day with it sored ya up some. As you know I use a 243 now and I like it.
.22-250 or the .25-06. opinions on which is better? Would be for an all around varmit rifle.
Of the 2 you mentioned the .22/250 would be best - the key words are "all around". The .25/06 is a great cross over cartridge when deer are on the menu. Ditto on what ChesterGolf said about the .243, one my all time favorites.
Understanding wind currents and thermals in hilly, broken terrain can often be incredibly frustrating. I've found that collecting and storing milkweed seed pods during the late summer has made me a better hunter in the bluff country that I hunt. These little feather like seed dispersers will float on the lightest of air currents and will show you what the wind is not only doing right at you're location but more importantly down range. I like to use the off season to float them...