I'd look for something along the lines of...
3-18
6.5-20
5-25
I run 6.5-20 and 8.5-25 on my .204 varmint rifles, but the only walking they see is from the gun case to the shooting bench. As you already know, anything above ~18x is worthless on a sunny day in the prairie dog patch. I enjoy using the higher magnification when punching paper, though.
