With the villager improvements coming soon, I had been thinking about what villagers can't currently do that could be pretty useful in the update. So, what if villagers could use fencegates, trapdoors, or ladders? As an example for fencegates, farmer villagers would be able to harvest crops from protected farms, so that only pesky players will trample the crops, and at night, zombies can't get in. (Edit: With Ravagers destroying crops during raids, this could be very useful) Villagers climbing ladders could be used for two story player-built houses. The first floor for work, the second as home. Pair this with a possibility of setting a villager's home to return to at night, and we're in business!
(Edit) It may also be useful to still be able to black villagers from entering certain areas, so what if there was a "villager locked" door? Crafting a door, Trapdoors, or fence gate with a sign of it's wood type could locked the door for villagers, simply adding a sign with a villager's head crossed out on the door, and villagers won't go through that door, fence gate, or Trapdoors. Zombies would still knock down lock dooors on hard difficulty.