The Glare

The Glare is a mob which will get grumpy if a place is dark for monsters to spawn, it looks cute and all, but considering there's an F3 Menu, it's kinda useless. It would be helpful to bedrock players though because it doesn't have F3 Menu

The Allay

The Allay will give you more of the items which you give it. It's not a duplicator because that will defeat the purpose of Minecraft, The way it works is that if you give it an item (eg. cobblestone) it will look if there are any of that block dropped around and will give it to you. It would be cool if there was a friendlier version of a Vex.Good for item sorting, A really useful mob, OH AND IT DANCES TO NOTE BLOCKS!!!!

Copper Golem

Copper Golems are Little Golems that loves to push copper buttons and will Oxidize and freeze over time. We don't have that much of Golem type mobs (are Wardens and Ravagers Golems?) A really useful mob if you make Redstone Contraptions

Conclusion

Either the Allay should win or the Copper Golem should