For 2CC Trams, we're finished for now. However, 2CC Cargo Trams could probably use some more vehicles. Most cargo trams were not purpose created, but were cobbled together by operating companies who pieced them together from wrecked and salvaged passenger trams (typically much older and obsolete equipment for passenger revenue service) in order to suit their own needs. It was pretty common to rebuild a car, gut the passenger seats, and either close in all the windows and doors to make a box car, or to just seal off the operating cab and turn it into a flat car, or attach equipment to the deck to turn it into a work truck like a tower ladder, boom truck, crane or side-dump trailer. But, some companies like Brill, Jewett and Kuhlmann did build purpose-built work equipment. Some examples I've found include refrigerated meat cars for South America, tanker cars, plows and brooms to clean the railways, freight motors (cargo & mail vehicles), etc.
Our biggest challenge here is finding documented photos and specs. Lots of people have documented this info for passenger cars, but work vehicles don't typically get this type of attention.