As you can see Obito is fodder compared to Kakashi if Kamui isnt included and since he can use Kamui more efficiently then Kakashi it makes him High Kage level or close to God Tier without it,makes him Chunnin Level or Jounin at max.
Kakashi with Kamui makes him Mid-High Kage Level
Obito with Kamui makes him High Kage Level-Close God Tier
Kakashi without Kamui=Jounin or Low Kage Level
Obito without Kamui=Chunnin-Jounin level
As you can see Kakashi threw 1 punch and made Obito spew up blood and look worn out.