I was thinking about this variant reflecting on a comparison between a battle and a chess game.
A chess game is much like a cruel battle in wich both the commanders have a clear and precise perception of the forces and their position.
In a real-world battle it is almost never so. You cannot state exactly where are and which are the resources of your enemy, and somtimes you are not so sure about your forces and where they are positioned (think, for example, at Bonaparte in Marengo or in Waterlo).
I've noticed that knight/bishop power reversal, too....... I guess the knight will still be strong, just limited in range. Your variant sounds cool, too, kipos. You could call it "Blind Chess"