fixed power scopes really stink for predator hunting, unless it is a 2x or a 4x, 6x is too much for shots within 25' and often not enough for shots where you can only see a yotes head sticking out over the top of a bush staring at you. I too keep my variable set on 4x-7x quite a bit, but yotes do hang up past 300 and will more often than not but a bush between you and them only giving you a partial body shot.
Of course, the type of terrain that you hunt in is what determines the kind of scope you hunt in.
3-12's and 4x-12, or 4-16's are much better choices than a fixed power of any kind(depending on your hunting terrain, of course) with the great compromise in budget constraints being a 3x-9x.
My varmint rifle is not just a yote rifle but crows, rabbits,chucks, p. dogs, musk rat, beaver, what ever in any kind of condition kind of rifle.
For many years the Leupold 3.5-10 was used as a "standard" in the two Varmint Hunting Clubs I was in. As the years pile on, I found my wanting more power not less. I can only remember two times where yotes got in to within 3 feet of me where 4x was too much, and I don't think that it would have mattered because the brush was so thick, they were right at the end of the gun barrel laying in my lap one second and disappeared around a bush the next second.
If I were hunting the thick with scattered open spots that allow for longer shots, I have a rifle set up with a 2x-8x on it. If you are hunting the thick dessert brush, a shotgun will give you the edge over a rifle...learning that lesson cost me many yotes.