Too fast and hax, Naruto and Sasuke work cooperatively and well together, enough to make Ichigo's and Ken's team-ship look horrible (assuming Ichigo and Kenpachi don't have any type of partnership.)
Naruto and Sasuke are both more powerful in DC and power, especially Naruto with his casual Bijuu-Rasen-Dama's and Sasuke's Perfect Susano'o combined with Amaterasu.
There's also teleportation, precognition, Senju enhanced lightning blade, and Amaterasu too add.
Naruto has clones that are equivalent to the original Naruto, each capable of pulling off the same feats as Naruto did.
Naruto also has flight.
Molecular destruction with the rods and orbs.
Genjutsu for Sasuke.
There's simply too much the team has, Ken and Ichigo will be too overwhelmed and eventually die because of bad partnership.