Glad I could help. Regarding your idea, this sounds like a very interesting thing to test. Having the Ctrl key slow down time in a game that's truly hectic but having limited amount of slow down sounds really fun! However the only way to know is to test. In my experience game design is 99% playtesting and 1% ideas. I encourage you to try this, it's great exercise and you already have a pretty solid mechanism to work on.