So let's say you have RCE and you can target two figures. Can you use RCE for both targets?

No. If you use RCE, you can only target one figure.

Unless the power has changed radically (I don't have my Batman Starter PAC on me).

RANGED COMBAT EXPERT Give this character a power action. It makes a
ranged combat attack against a single target character; modify its damage value by +2 for the attack.

Single target only.

The simplest rules often get over looked. This is one that even I find myself double checking from time to time.

This is absolute proof why it is a good idea to quote the power in question

Often the answer will be right there in black and white
Less often it will be revealed that you are using an outdated PAC or are paraphrasing

It has not changed. Single target only.