May not be high on the priority list but environment interactions and like interactive foliage etc,some form of basic weather system that ties in to some survival elements like being cold on a rainy day or being dehydrated on a hot day.Environmental hazards too would be cool and illnesses that can affect the player.
I would also like to see some AI related stuff.Having watched the videos you said your steering away from making zombies so it would be cool to see how to make various NPCs/mobs that behave and act differently from each other and maybe also interact between themselves.
Also would it be possible to tackle modular pawns in UE4?Possibly tie in with the inventory system your making?
I just found out about the stream today and I must say is very helpful and enjoyable to watch.Would try my best to catch up with you on your next stream.Cheers