Hiruzen's best feat is sniffing out Hokage's within close proximity (not to mention he probably already was familiar with their scent given they were his teachers). Kakashi emulated that when he was a kid in the Gaiden.
Having good chakra control isn't a placeholder for unlimited stamina. Alive Hiruzen used a Katon, a Doton, summoned Enma, KB shuriken, and used two Kage Bunshin before dying. Kakashi was able to use two Kage Bunshin, eight Raikiri variants, a Doton wall, and five Kamui before getting tired, and we know Kamui is far more exhausting than any of the other jutsu. With Kamui restricted, Kakashi has far more flexibility with his base arsenal.
Kakashi defeated Zabuza with Genjutsu. It was proficient enough to force Gai to develop an entire fighting style just to counter his Genjutsu, despite knowing the Kai method (and using it to escape A-ranked jutsu). It was powerful enough to match Obito's Genjutsu, whom was able to Genjutsu a perfect Jinchuuriki for years.
Sharingan provides precognition and Genjutsu prowess. Telling me "it's been beaten many times" isn't an argument, especially when a large portion of those "times" were against a superior Sharingan user, a Sage Mode sensor, or a top tier speedster, none of which Hiruzen is. You'd have to explain what Hiruzen actually does to "beat" or "stalemate" it.