The versus is actually a pretty decent complete right out of the box. I would say ride it as is until something starts to wear or break. If you really want to upgrade and make it a custom, I would look into cranks, stem, and wheels. But im sure you could get good use out of the stock components.
Maybe a sprocket if it has the shitty steel one on it.
ya man my stem woudlnt look good on this i would sudgest a yellow or arange stem and to take off the brakes if u havnt already becuz it wares ur rim color then thy look lik garbage after wen u use ur brakes,....... and start off small with the bike like by buying tires and grips an stuff then for xmas or bday get big stuff for it like rims and frame an crap ///////........... JUST DONT FORGET TO RIDE THE BIKE
yeah i took the brakes off and i rlly cant ride it cuz im recovering from a broken wrist plus there is tons of snow and i kinda just want ppurple parts plus i hated my barends so i have white kink ones
Elmira, Ontario, Canada 
Maybe a sprocket if it has the shitty steel one on it.