Personally, I can't really choose any favorites, cause I love them all so much. But if I were to pick a few that I particularly favor, then I'd have to say that I love Shikijiki and Mebukijiki, Hiyappu, Tsutaja's line, Mijumaru's line, Desukaan, and Monmen quite a bit. Coming in second to these ones are Buffalon, Tabunne, Churine, Tamagetake, Denchura, Munna and Musharna, and Choroneko.
Now if you want my favorites among the unconfirmed/rumored pokemon, I'd have to say that I like the ice cream, the garbage bag, the polar bear, and the candle line. Also, I think it goes without saying that a fire type anteater is FREAKING BOSS.