There are already some timed events. For example, taking a long rest after encountering the burning house, will not let you save anyone because they're all burned up, and so you miss out on one quest. I think its fair. However, some of such timed events if subtle, should give a sense of urgency to the player via dialogue, one great way to get bummed out is to get an update about being too late when the player may miss out or forget about such quest/event.
