Skills question - am I too reliant on orthographic views?

Sastrei

I've realized that while I keep getting better at actual poly modeling, I'm pretty much useless without a concept sketch to work from and at least top/side orthos to get me started. I just don't have a good eye for proportions or much in the way of an artistic sense. While of course I should overcome this, how much of a hindrance is this really? Is it normal to expect concept artists to generate at least one ortho view, or should a 3/4 sketch be enough to create a finished model from?