Abomasnow has fallen to UU and when he was OU was certainly not one of the best Pokémon in the tier. He was/is a neat answer to weather, but hardly worth being called "one of the best". Very tough to use effectively and SR weak with a massive amount of weaknesses, one of them being to U-turn, Abomasnow is quickly worn down and beaten while offering lame stats all around. It doesn't help that his Wood Hammers give him recoil too.
I've started running Rain stall recently and have found that if the opponent has no weather I tend to use Politoed as death fodder. I feel I can essentially beat teams 5-6 thanks to that rain support. Rain in particular really gives a ton of already great Pokémon (Ferrothorn, Jirachi, Tentacruel...) an advantage that's quite difficult to overcome without the ability to cancel Rain. I'd like to see a meta without Drizzle and see if I feel the same way about Drought. But at the moment the real concern to me and many others is that Rain is so effortlessly powerful. I think non-weather is viable, but it's very, very limited in what it's allowed to do because it needs to be so ready to function in weather, especially Rain.
&Mikel: i'd eat dog