I'm thinking of bringing the same thing to each potluck
Why would you be so repetitive on your dish?
"I'm thinking I would reward myself for my hard work
You want to reward yourself by bringing the same food to a potluck, but that can be boring. Reward yourself deep down moreso with being creative and offer different meals. That way people can't guess what you will bring every time because it's the same thing.
Hmm, maybe I should have a little more fun.
How much do you enjoy cooking? If you like it, try new things but If your dish is your signature dish, then maybe bring it is the best thing. Do what makes yourself and other happy.