Unless u want to constantly download multipls gigantic files (50GB and above) everyday in a short amount of time... 100Mbps package is more than enough for around 4 people (with 1 heavy-user).

Streaming 4K should be ok as well, mayb 2 users max?

Online gaming of course 100Mbps is more than sufficient (ping and packet loss is more important here) - Dota on 4Mbps was possible some years ago (although once in awhile connection would timeout huhu)

Anyways, it's human nature to always ask for more... last time when Time Fibre offer 100Mbps all of our jaws dropped lol