The thing is, there is no right answer. With five separate series in the same world, I tried to write each book in a way that someone could jump right in from that starting point. If you REALLY want a list, here are four possible routes through the world.
Strict Chronological Order:
If you're a purist, you may want to read the stories in the order they occur. This is the strict timeline for ALL the books in the Supervillain Rehabilitation Project Universe (note: The DOSA Files anthology includes multiple stories set at different points in the timeline. The short story "Rethink" is technically the earliest point in the timeline, but since the stories in this collection are not essential to the whole and they all occur in different years, I don't list it as part of the timeline. You can read it at any point).
Relapsed
Reformed
Redeemed
Reborn
Refined
Blind Date with a Supervillain
Power On
Reunion
Power Play
On the Run with a Supervillain
Power Through
Power Up
Superhero For Christmas
Superhero Ever After
Captured by a Supervillain
Engaged to a Supervillain
Accidentally a Supervillain
Second Chance Superhero
Wishing on a Supervillain
Her Fake Superhero Boyfriend
Rescuing a Supervillain
Courting a Superhero
Game On
Game Changer
This route was actually suggested by some of my younger readers. If you are primarily a YA reader, you may want to start with the Supervillain Rescue Project teen series. Once you do, though, you may want to continue to follow that series's lead character, Jake, through his journey into adulthood. This is the route that chases Jake through his character growth from angry young man to responsible and steady husband and father.
Power On
Power Play
Power Through
Power Up
Captured by a Supervillain
Engaged to a Supervillain
Accidentally a Supervillain
Game On
Game Changer
(the rest whenever you get around to them)
The "I LOVE A TWIST" Route
I'm actually not a huge "twist" writer, but there are three events that happen throughout the series that can be spoiled if you read in the "wrong" order. This is the order you can take that will provide you the most surprises.
Relapsed
Reformed
Redeemed
Reborn
Refined
Blind Date with a Supervillain
On the Run with a Supervillain
Captured by a Supervillain
Power On
Reunion
Power Play
Power Through
Power Up
Engaged to a Supervillain
Accidentally a Supervillain
(you can fit the romance books anywhere, just be sure you read Wishing on a Supervillain BEFORE Game On)
So maybe you're in it JUST for the kissing books, and you don't really care about anything else. That's fine. This the route to maximize the romantic feels.
Superhero For Christmas
Superhero Ever After
Blind Date with a Supervillain
On the Run with a Supervillain
Captured by a Supervillain
Engaged to a Supervillain
Accidentally a Supervillain
Second Chance Superhero
Wishing on a Supervillain
Her Fake Superhero Boyfriend
Rescuing a Supervillain
Courting a Superhero
(go back and hit the YA and main series if you feel like something less kissy/kissy)