well, im not any pro since im playing less than a month dota, but why the fuck you say "chogath is unbeatable etc." You can easily destroy him at early game.
I have played like 4 champs: Jax, Zilean, Singed, Shaco and Malzahar.
My favorite one is Shaco ofc, my gameplay style is diff at all other i have seen through internet etc.
Im becoming a pure stealer with him.
I like malzahar too, the only bad thing with him is that he cant faking escape from ganks <.< except your enemies are too idiots and you try to silence or treat them with some "poisons"