I think that I agree with a lot of the people taking issue with Blade Ward’s place in the action economy. It might be better to add a risk, like potentially wasting your reaction.

To be more clear, I’m suggesting that you change the casting time to “1 reaction, which you take on your turn” then make the duration 1 round (I understand that this was a typo) and only have the effect apply to the first attack your recieve ‘til the start of your next turn. This way using the cantrip isn’t nearly free guarenteed resistance and has to be used pre-emptively, potentially wasting their reaction that could have been used for another spell, readying an action, or making an opportunity attack.