I wouldn't really say that Aya is a low profile character. She's definitely not the most known character from Playstation, but among us who grew up in the '90s, she's very well known. One of the reasons she isn't well known is because the gaming industry hadn't really taken off yet and you didn't see sales back then like you do today. She was popular for her time. However, since the release of The 3rd Birthday, I believe her popularity has grown and I've always felt that Aya was a kind of icon of Playstation. She could be very unique. You want to know a low profile character? Claire Redfield. A lot of people don't like her. Look how scarce she is in the RE universe.
Level 1: Rocket Launcher. Pretty self-explanatory and simple. Fire a rocket and kill an enemy.
Level 2: Barrier Ability. Aya won't spurt out red orbs for a set period of time. 20-30 seconds.
Level 3: Liberation. I can't think of how to make this work but it needs to be her level 3 special. As long as it's not the Liberation from The 3rd Birthday.