Well, I can answer your question. I am a real life engineer, & I design Automotive components as my day job. I self taught 3D, & mainly focus on Character design, until I decide to make may own game, when I put most focus on environments & props. looking at the content creations here, & an experience poster at CGTalk 3D session, characters, organic things & monsters are the hardest things to model for most people. You do not required strictly good drawings skill, but most character artist have decent drawing base, proportion, anatomy, these skills are usually transferable in some form.
But to made geometry shapes from existing designs, like a table, you do not need that much art skill, you just need blueprint, & take the correct dimension. CAD designer do not strictly required any art skill of note, same can be said of 3D design for many things (table, chairs, Cabinets, doors etc), you just need to tune in to how 3D wireframe modeling works, teh same way a CAD designer can trace the base shape to make the design. Of course if you want to make intricate classical Gothic style design, then you need major art & design skill. Your typical Ikea style table, not as much.
Get someone to help design your characters, & you create the rest will be a good start.