modern knight deck, viable?

You have a lot of good pieces, but literally NO answer to opposing threats.  Path to Exile strikes me as a very important piece.

Given the aggro nature of what you have, I would suggest dropping Elesh Norn, dropping Hero of Bladehold to 2x and moving Kinsbaile Cavalier up to 4x as giving ALL your creatures double-strike is more important than pumping out tokens.

Perhaps Adaptive Automaton could serve you well... might as well pump things while you can.  The only other hole I can think is the lack of any card draw (typically a challenge in most colors outside of blue).  As you're going to dump your hand quickly, you'll end up top-decking a lot... some of these knights aren't exactly the bombs you would want to draw beyond turn four or five.

thanks for the comments already. going to drop elesh norn as she requires too much mana for this deck as well

path to exile is a very good which i'm going to place in the deck. also chaging the number of cavaleries to 4

Even with 4x Path to Exiles, this deck is still lacking answers to a lot of things.  I'd probably also slip in some Oblivion Rings to have something to deal with artifacts and enchantments (or even more creatures). 

You may also want some more options for flying.  With only four flying creatures in your deck, you'll be hard pressed to fight back against any kind of flying token deck.