Welcome to the forums,

The nemesis doesn't need much upgrading, it's a real durable and strong truck. The only upgrades you need to buy to start are a stronger steering servo, the updated axles(part# GS028) the stock ones are real thin and break easily. And the other upgrade is the Ofna fuel pump and primer(part#10168) this will help your engine run more consistantly through the whole tank of fuel because the Nemesis and GST both suffer from the Half tank lean issue.