Batteries are slung under the chassis. (better center of gravity)
Motor is mounted transversly (180 will not fit)
Additional gear in between pinion and final drive (more ratios)
Car is sealed up when assembled (keeps a lot of dirt out of drive train)
Second lighting accessory plug (ground lighting)
Chassis can be lifted or lowered (Better cg
or gc
)
Electronics will take a heavier load than the Gen1 cars. I don't recall off the top of my head just how much they can tolerate.