Playing with 3d modelling will help you understand the forms involved and how light plays across them.
What it will not do is grant you speed or consistency. In your position, where you have many different ships to design and render, having a really solid understanding of forms and perspective is really the primary thing that will let you do that in a reasonable time frame with reasonably consistent results.
tl;dr: if I was in your position, I'd use blender as an educational tool, to understand form, perspective and perhaps lighting better, but not as a direct part of my workflow.
If you want some more direct advice: break everything down into boxes. If you can draw boxes in perspective, it's relatively easy to draw other shapes like ramps, curves, cylinders, cones, and spheres that can be fitted inside that box. Same thing with lighting -- if you can light the box correctly, it's not too hard to approximate the lighting for any other simple shape from that.
Also if you're struggling with perspective don't bother with making it specifically as pixel art -- you can always do that once you've worked out how the perspective should work with a much looser drawing.
