I am also a Certified Unity Gameplay Programmer.
Computer Game Design
I have a BA in Digital Art and Technology (Game Design) and have taken game systems from vague brief to complete product. I know my Bartle's Taxonomy from my Engagement Curves, I read game design books for fun and study games to see what has and can be done in the medium.
Board Game Design
I've also researched and worked on multiple board games, attending game jams with flashcards, sharpies and bags of meeples. I've created hidden movement games, drafting games and push your luck dice rolling games. I write design docs and balance game content with somewhat excessive spreadsheets.