For example, Karl Lunt, Marvin Green, Tom Dickens, and myself did this with the BotBoard Plus design. I have other teams for other types of designs. For each design, I try to select people who I trust have some technical knowledge or experiences that I feel are better than my own. As I work on my feature list, lots of different ideas flow through my head, are evaluated, and sorted into a priority list. When you design your own board, you will be full of self doubt about which features are important, and which are not.
Self doubt is quite normal and just part of the design process.
Here are a few things to think about while working out the feature list. I like to think I am a pretty decent engineer. As such, I can make systems just as complicated as you can imagine. However, I am also an experienced engineer. I know that whatever I come up with, you are going to want something slightly different, or won't want most of the features I put on board.