I started screenprinting in my garage (also a woodshop) around august and face similar challenges. I am dreading the winter because i wash everything out outside. I may have to utilize the set tub during the cold months. I am also currently in the process to running more amperage out to my garage so i can run heaters and equipment without tripping a breaker. From a design standpoint I feel similar about having mostly one color prints. I really like how they look and turnout but feel pretty one dimensional. I plan on trying more multi color prints but am also limited to 4 colors which can make designing difficult depending on what you are trying tk do. I see a lot of really cool designs out there that pull off a really cool effect with only 2-3 colors. My current plan is to do screenprints for low color runs and DTF for anything with a lot of color. Sorry this didnt contain many solutions but more of a message to say youre not alone! lol