Depends on what I want to achieve... If I want a sky base i'll chose jungle since i love the big trees, for anything else spruce forest seems good enough
All the snow'ey ones Snow is just beautifull reminds me off great times of old alpha and this climate just little wooden stylish house which was something great ;3 i still love snow even in real life
My favorite biome for sure is the "Mesa" in addition to the bright colors it has, if you add mods of applied generation all biomes included it will be even more beautiful with shaders to improve even more