Breakout is a great candidate for a toy game. As is snake. I often make Breakout clones to familiarise myself with new systems.

If you're looking to get things done fast I think Unity is an excellent choice. After coming from years of working with custom engines and Frostbite, Unity feels like such a breeze.

As for r/gamedev I'm quite active there myself and while I like it and it's gotten a lot better recently it still has an issue where it's largely hobbyists and inexperienced indie developers. Their uninformed opinion will often drown out more qualified voices. So take information there with a grain of salt.