What about a notification digest, where the user gets a list of updates every (day|week|<configured duration>)? Perhaps after explicitly requesting to receive updates about so-and-so. This allows the user to decide, "At 20:00 each night, I'll get a list of new stuff from my friends, and I'll take some time and peruse it," rather than getting blasted at odd times.
>>floren+(OP)
I wish this was an OS level feature on my phone and computer. I will often disable notifications from, for example, Slack on the weekends, and every time I do I silently wish there were a way to automatically control notifications per app based on time and day.