The flip-flops are implemented like that. They're mostly a bunch of NAND gates behind the scenes. In the future, I plan to let anyone create a sub-circuit, but that has some challenges that I think I'd rather face after I make the first desktop release.
The biggest slow-down is intentional, though. Since the wires are colored, propagation is currently limited to the frame rate so that all changes can be seen. Some circuits, like the oscillator sample, look pretty strange when propagation isn't tied to the frame rate. I plan to add a setting to turn off wire colors, and then I'll probably make the propagation adjustable too.
The biggest slow-down is intentional, though. Since the wires are colored, propagation is currently limited to the frame rate so that all changes can be seen. Some circuits, like the oscillator sample, look pretty strange when propagation isn't tied to the frame rate. I plan to add a setting to turn off wire colors, and then I'll probably make the propagation adjustable too.