Well, pretty much all of Sasuke's Ninjutsu are countered because of Pains Preta Path. amateratsu, chidori(in any kind of form), any other fire style technique, etc.
His taijutsu while impressive, is not on par with Naruto's in sage mode IMO. He won't be able to get in close anyways because of Deva Path and with Asura Path granting cover and protection. Even if he does, the pain's share vision with one another, thus making them almost impossible to hit.
Susanoo' although never been proven, could potentially be absorbed by Preta Path as well, as far as we know Susanoo' is made of chakra which leads me to believe it can be absorbed as well.
The only thing he has going for him is genjutsu, this in itself is a gamble against such a high level opponent. The fact that each of the six paths don't feel pain, Tsukyomi won't really effect the bodies themselves. A paralyzing genjutsu could render one of the bodies useless, but it can be revived later. In addition it can be snapped out of the genjutsu by one of the other paths.
I just don't think Sasuke is a good match against Pain, honestly not many are. Pain is still to date one of the strongest character's in Naruto, he's not called the reincarnation of the Sage of Six Paths, and a God for nothing.