I am working on the 28mm Viper Suit, and getting the Hot Wheels bits printed (they're fiddly!)
But, 15mm tanks also inhabit my brain. Big ones, since I'm not regulated by the size of vendor printer bills anymore (within reason, of course).
Here's a possible next project...The Mega Merka. Merkalodon? ;)
Hull is just over 5 inches (approx 125mm) long. Merkalodon...that's catchy.