Seeing as Itachi already defeated Oro without trying in roughly five seconds, no, not really.
Orochimaru was dying and trying to trade bodies without killing Itachi. Sasuke has the exact same feat.
If Orochimaru were healthy and trying to kill Itachi, he'd be dead. Orochimaru has counters to all of Itachi's abilities and has ways of taking Itachi out.
Itachi used Amaterasu on Nagato and he was unable to do anything. If it wasn't for Shinra Tensei, he would of been immobile.
You're underestimating how fast Amaterasu moves. Oro won't be able to use the Rashomon before Itachi hits him with Amaterasu, and he won't even know when he's going to use it. And after that picture I showed you, I think it's safe to say that Itachi can use the black flames more than Oro can use body shed.
Nagato wasn't able to do anything because Edo Tenseis aren't allowed to act or react to other Edo Tenseis, Kabuto had to override Nagato so that he could use Shinra Tensei and get rid of Amaterasu, Nagato also had crippled legs and couldn't move very well.
You're overestimating it. Sasuke ran from it and Gyuuki blocked it with his tail before it hit him. It's also easy to notice Amaterasu coming; Itachi closes his eyes for a few seconds and it starts to bleed before he uses Amaterasu.
Itachi has about 5 uses of MS, and each time he uses it his chakra drops greatly and his condition worsens. Itachi actually has to be more careful with it. Orochimaru on the otherhand, aside from body shed, can dodge or use other things to intercept Amaterasu.
I never suggested that Orochimaru could use Mokuton. . . cause he can't. The only win I see Orochimaru is winning via attrition since he has nothing that can damage or harm Susanoo.
Orochimaru can get under Susanoo since that's Susanoo's vulnerability. Orochimaru uses Leech All Creation to get under Itachi, then extends Kusanagi up through Itachi.
Orochimaru could emerge inside of Susanoo too where Orochimaru has the advantage. Susanoo can't reach inside itself and an Amaterasu at that range will catch Itachi on fire too.
Orochimaru can also use summons to wrap around and constrict Susanoo's movements, making it so Susanoo can't do anything except protect Itachi until Itachi runs out of time.
Also, the poisonous fumes from Orochimaru's blood should still paralyze Itachi.