They aren't really important as characters. They're basically plot device to understand and connect Uchiha and Senju. But as the others pointed above if you're that interested in them just look at Sasuke and Naruto, they are the Indra and Asura of today.
I hope so, it might be cool as a flashback somehow between Naruto and Sasuke.
Personally I just want to see what actually happened between Ashura and Indra. So far we have a beginning, a middle, and a highly ambiguous end. I bet Kishi has more in store about these two, probably just to as a link to Naruto and Sasuke though.