Obviously he didn't have the Kyuubi, but how powerful do you think he was at this stage?
At 16 he was weak
"Run on sight"
"Konoha's Yellow Flash"
Minato died young, so he most likely got that moniker in his teens. At, about, 10 he shat on those chunnin-jounin kidnappers that came for kushina. Guy was a bigger beast than Naruto by far. Take away Kyuubi and naruto's near fodder. 17 year old minato would most likely easily compete with an SM naruto.