This kind of ruins Davros' character. If he, as a result of the war, winds up horribly crippled, blind, and in a wheelchair, it makes sense that he would be driven to create machines to provide mobility and survival to what he thinks is going to become of his race. I won't go so far as to say he's a sympathetic character, but you can at least understand his motivation and how, from his perspective, he's doing the right thing. But if he's completely able-bodied, then he's just a "MUWAHAHAHAHA! EEEEEVILLL!!!" cardboard character who wants to cripple and disfigure his own people because, reasons.
I say again, the reason Khan is such a good villain in TWoK is because Montalban played him as the hero; in Khan's eyes, he's doing the right thing.