Nuclear Reactor. A Nuclear Reactor would function like a Battery Compartment or Super Capacitor but be SUPER heavy (despite being the size of the Sloshy T 1500) never need Recharging and Recharge Battery Compartments and Super Capacitors.
Plazma Drive (misspelling on purpose). Plazma Drive would be a ridiculously heavy and powerful Engine consuming Fuel and/or Power at equally ridiculous rates. It would not be compatible with a Nuclear Reactor. (perhaps because of instability over 60% output?) I have a name in mind for it; Thunderstorm 6000. It's description; Experimental high output Engine. Details Top Secret.
Super Huge Fuel Tank. A Super Huge (and heavy) Fuel Tank would work well with the Plazma Drive. I have a name in mind for it; Titan T 20000.
I figured some Super Parts that deliver extreme performance at the cost of extreme weight would be a nice addition to the game.
KNOW ALL; I do not claim to be the first person to come up with and post these Ideas.