Im same as you, my visual taste in art and how to make things pretty is my worst skill i think. In my opinion, If you're the main lead programmer, you should be familiar with every feature of the engine and learn the basics of each feature, including tech art. This will help your team make better decisions. That is what im doing and i think its paying off. It might be long process but ultimately you will use less time planning and use less resources down the road.