Even in design school, professors would say “You’ll be judged on the level of your presentation” and that will still be true for how you present. Even a 5 minute Keyshot rendering on some basic cad will make the design look “finished”.
Sometimes it’s valuable to keep that sketch, or present renderings in a “Sketch” format (render in a white diffuse material, add some pen strokes after the fact, and throw some penned in notes on top) so that it doesn’t make it as obvious that you already have a full 3D database ready to go.
That’s one nice feature about Alias - they make it easy to use your 3D curves to “Snap” to if you’re willing to learn their legacy sketching tool. I’ve seen some people use that method very effectively. Nicely polished lines and line weight with accurate shading, but it doesn’t look like a finished production database ready to ship to engineers, so people are willing to treat it the same way they’d treat a sketch.