EXWM: Emacs X11 Window Manager
Some features of EXWM include: treating every single application and window like a normal Emacs buffer, using simulation keys to get emacs keybindings (or whatever your preferred bindings are) anywhere, having emacs shortcuts work even when within another application, and also having your project management and window management rules and packages apply to your entire desktop as well. If you're an emacs user, I highly recommend trying out EXWM alongside configuring your web browser to have one tab-per-window. It makes using any other window manager or interface feel like a pain in comparison.
Permadeath in Rita's Rewind
This made the game a lot more enjoyable to me, especially when you turn on the tougher or maximum enemies modifiers. It also gives the game's "continue system" a reason to exist rather than just being completely useless. I also added the rule that once I beat a stage, I can't go back, meaning if I don't get an S-rank score or get all the collectables, then I'll just have to try harder in my next play through. I was inspired by the idea of making Mighty Morphin Power Rangers: Rita's Rewind feel more like a classic arcade game by emulating losing one and also deleting my save after every game quit.