Really glad you enjoyed the game. How can one go wrong with West Coast Avengers and Cortex Prime.
A quick apology, I should have spent a couple of minutes talking about what we were doing mechanically. So, here goes.
Yes it is different from Marvel Heroic, though it also shares some things with MHR.
First, about the system, the way Cortex Prime works is that it makes all of the elements from previous versions (with updates and improvements) available, and Cam has made them into a toolkit to use what you want to make the game that you're after. (This is one of the things that I really love about Cortex Prime.) So, for WCA I used some similar things to MHR. I used Affiliations, Distinctions, and Powers. What it really came down to is that I wanted players rolling 2-3 dice for rolls with the option to add a fourth die. Then they add 2 dice together to get a result. If they are affecting an inanimate object or overcoming some obstacle I gave them a static difficulty number. If they are acting against a person (or some such) I roll against them. Bad guys are given a "rating die". So when I'm building the dice pool for the bad guys, It's the difficulty of the scene (Typically a d8-d12), the rating die of the bad guy, and then I can draw from the doom pool to add dice to the pool. Every success that they get that would "damage" the bad guys steps down the rating die for the bad guys until they come off the table.
The idea is to make for a simple and easy system to set up and run to give a heroic comic book feeling.
Second, about the characters:
Taking some advice from a friend who is MUCH better at running Cortex than I am I wanted characters to be more about distinctions than anything else. But in a game about a group of disparate individuals coming together Affiliations are relevant too. For example, Kate is at her best when she's working in a group, but Gwen is at her best on her own, and Quentin wants to be better on his own but he's not. I built the characters largely from the note bubbles in the comics. (If you haven't read them I highly recommend them)
Powers are a bit tricky in Cortex in my opinion because it's easy to get overpowered with them, or make them not really relevant. Making good distinctions and good powers is kind of an art form that I'm still trying to learn.
Not sure if I've answered your questions here, if there's anything else I can provide I'll be happy to do so.